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                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 10-QSB

             (X) QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF
                       THE SECURITIES EXCHANGE ACT OF 1934
                  For the quarterly period ended March 31, 2004

                                       OR

              ( ) TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934
               For the transition period from ________ to ________

Commission File Number 1-31398

                        NATURAL GAS SERVICES GROUP, INC.
        (Exact name of small business issuer as specified in its charter)

            Colorado                                             75-2811855
(State or other jurisdiction of                              (I.R.S. Employer
  incorporation or organization)                             Identification No.)

                                  2911 SCR 1260
                              Midland, Texas 79706
                    (Address of principal executive offices)

                                 (432) 563-3974
                (Issuer's Telephone number, including area code)

                                       N/A
     ----------------------------------------------------------------------
              (Former name, former address and former fiscal year,
                         if changed since last report)


Check  whether the issuer (1) filed all reports  required to be filed by Section
13 or 15(d) of the  Exchange  Act during the past 12 months (or for such shorter
period than the registrant was required to file such reports),  and (2) has been
subject to such filing requirements for the past 90 days.

                                    Yes X  No
                                       ---   ---

                      APPLICABLE ONLY TO CORPORATE ISSUERS

State the number of shares outstanding of each of the issuer's classes of common
equity, as of the latest practicable date.

                                                           Outstanding at
            Class                                          March 31, 2004
-----------------------------                      -----------------------------
Common Stock, $.001 par value                                 5,379,835
                                                   -----------------------------

Transitional Small Business Disclosure Format (Check one): Yes    No X
                                                              ---   ---

================================================================================



                        NATURAL GAS SERVICES GROUP, INC.


Part I - FINANCIAL INFORMATION

Item 1.  Financial Statements
-----------------------------

Unaudited Consolidated Balance Sheet......................................Page 1


Unaudited Consolidated Income Statements..................................Page 2


Unaudited Consolidated Statements of Cash Flows...........................Page 3


Notes to Unaudited Consolidated Financial Statements......................Page 4


Item 2.  Management's Discussion and Analysis or Plan of Operation........Page 7
-------

Item 3.  Control and Procedures...........................................Page 9
-------

Part II - OTHER INFORMATION

Item 1.  Legal Proceedings...............................................Page 10
-------

Item 5.  Other Information...............................................Page 10
-------

Item 6.  Exhibits and Reports on Form 8-K................................Page 10
-------

Signatures...............................................................Page 13





                        Natural Gas Services Group, Inc.
                           Consolidated Balance Sheet
                                   (unaudited)
                                 March 31, 2004

                                     ASSETS
Current Assets:
   Cash and cash equivalents                                         $   196,138
   Accounts receivable - trade                                         1,049,088
   Accounts receivable - other                                         1,500,000
   Inventory                                                           3,263,642
   Prepaid expenses                                                      160,042
                                                                     -----------
              Total current assets                                     6,168,910

Lease equipment, net                                                 $20,942,965
Other property, plant and equipment, net                               2,873,796
Goodwill, net                                                          2,589,655
Patents, net                                                             107,070
Other assets                                                             103,400
                                                                     -----------
         Total assets                                                $32,785,796
                                                                     ===========

                      LIABILITIES AND SHAREHOLDERS' EQUITY
Current Liabilities:
   Current portion of long term debt and capital lease               $ 2,480,677
    Line of Credit                                                       119,251
   Accounts payable and accrued liabilities                            2,285,024
   Unearned Income                                                         3,111
                                                                     -----------
         Total current liabilities                                     4,888,063

Long term debt and capital lease, less current portion                 8,063,394
Subordinated notes, net                                                1,425,583
Deferred income tax payable                                            2,094,204
                                                                     -----------
              Total liabilities                                       16,471,244
                                      SHAREHOLDERS' EQUITY
Common stock                                                              53,798
Paid in capital                                                       11,228,899
Retained earnings                                                      5,031,855
                                                                     -----------
         Total shareholders' equity                                   16,314,552
                                                                     -----------
         Total liabilities and shareholders' equity                  $32,785,796
                                                                     ===========




The accompanying notes are an integral part of the consolidated balance sheet



                                                                               1

                        Natural Gas Services Group, Inc.
                         Consolidated Income Statements
                                   (unaudited)


                                                   Three months ended March 31,
                                                   ----------------------------
                                                       2004            2003
                                                   ------------    ------------
Revenue:
   Sales                                           $    889,965    $    565,272
   Service and maintenance income                       423,602         377,310
   Leasing income                                     2,254,784       1,401,163
                                                   ------------    ------------
                                                      3,568,351       2,343,745
Cost of revenue:
   Cost of sales                                        646,394         433,173
   Cost of service and maintenance                      336,250         335,301
   Cost of leasing                                      568,409         360,917
                                                   ------------    ------------
                                                      1,551,053       1,129,391
                                                   ------------    ------------
Gross Margin                                          2,017,298       1,214,354

 Operating Cost:
   Selling expense                                      177,389         138,947
   General and administrative expense                   488,259         380,166
   Depreciation and amortization                        526,685         361,966
                                                   ------------    ------------
                                                      1,192,334         881,079
                                                   ------------    ------------
Operating income                                        824,964         333,275

   Interest expense                                    (180,608)       (154,083)
   Other income                                       1,501,081          22,547
                                                   ------------    ------------
Income before income taxes                            2,145,437         201,739
   Provision for income tax                             251,698          83,856
                                                   ------------    ------------
Net income                                            1,893,739         117,883
   Preferred dividends                                   27,922          31,010
                                                   ------------    ------------
Net income available to common shareholders        $  1,865,817    $     86,873
                                                   ============    ============


         Earnings per share:
         Basic                                     $       0.37    $       0.02
         Diluted                                   $       0.36    $       0.02
         Weighted average Shares:
         Basic                                        5,065,327       4,857,632
         Diluted                                      5,221,441       5,059,456




The  accompanying  notes  are  an  integral  part  of  the  consolidated  income
statements.

                                                                               2




                        Natural Gas Services Group, Inc.
                      Consolidated Statements of Cash Flows
                                   (unaudited)
                                                                     Three Months      Three Months
                                                                        Ended             Ended
                                                                    March 31, 2004    March 31, 2003
                                                                    --------------    --------------
                                                                                
CASH FLOWS FROM OPERATING ACTIVITIES:
   Net Income                                                       $    1,893,739    $      117,883
      Adjustments to reconcile net income to net cash provided by
      (used in) operating activities:
      Depreciation and amortization                                        526,686           361,966
      Deferred taxes                                                       251,698            83,856
      Amortization of debt issuance costs                                   16,239            16,239
      Gain on disposal of assets                                              --             (14,979)
      Changes in operating assets and liabilities:
      Trade and other receivables                                         (232,493)         (335,448)
      Accounts receivable - other                                       (1,500,000)             --
      Inventory                                                           (709,403)         (658,519)
      Prepaid expenses and other                                           (53,012)          128,264
      Accounts payable and accrued liabilities                           1,213,472           146,651
      Deferred income                                                     (204,104)          106,385
      Other                                                                  3,273           (85,659)
                                                                    --------------    --------------
  NET CASH PROVIDED BY (USED IN) OPERATING                               1,206,095          (133,361)
   ACTIVITIES

CASH FLOWS FROM INVESTING ACTIVITIES:
   Purchase of property and equipment                                   (2,530,447)       (3,143,155)
   Distribution from equity method investment                                 --             291,843
   Proceeds from sale of property and equipment                               --             105,000
   Decrease in lease receivable                                               --              23,171
                                                                    --------------    --------------
  NET CASH USED IN INVESTING ACTIVITIES                                 (2,530,447)       (2,723,141)

CASH FLOWS FROM FINANCING ACTIVITIES:
   Net proceeds from bank loans and line of credit                       1,952,778         2,225,623
   Repayments of long term debt                                           (604,143)         (440,505)
   Proceeds from warrants exercised
                                                                            23,575              --
   Dividends paid on preferred stock                                       (27,922)          (31,010)
                                                                    --------------    --------------
NET CASH PROVIDED BY FINANCING ACTIVITIES                                1,344,288         1,754,108
                                                                    --------------    --------------
NET CHANGE IN CASH AND CASH EQUIVALENTS                                     19,936        (1,102,394)
CASH AT BEGINNING OF PERIOD                                                176,202         2,713,638
                                                                    --------------    --------------
CASH AT END OF PERIOD                                               $      196,138    $    1,611,244
                                                                    ==============    ==============

SUPPLEMENTAL DISCLOSURE OF CASH FLOW
INFORMATION:
      Interest paid                                                 $      180,608    $      154,083








The accompanying  notes are an integral part of the  consolidated  statements of
cash flows.


                                                                               3




                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

 (1) Basis of Presentation

         The   accompanying   unaudited   financial   statements   present   the
consolidated  results of our company  taken from our books and  records.  In our
opinion,  such information  includes all adjustments,  consisting of only normal
recurring  adjustments,  which are necessary to make our  financial  position at
March 31, 2004 and the results of our  operations  for the three months  periods
ended  March 31, 2004 and 2003 not  misleading.  As  permitted  by the rules and
regulations  of the Securities and Exchange  Commission  (SEC) the  accompanying
financial  statements  do not  include  all  disclosures  normally  required  by
accounting  principles  generally  accepted in United  States of America.  These
financial statements should be read in conjunction with the financial statements
included  in our  Annual  Report on Form  10-KSB  on file  with the SEC.  In our
opinion,  the consolidated  financial  statements are a fair presentation of the
financial  position,  results  of  operations  and cash  flows  for the  periods
presented.

         The results of operations for the three months ended March 31, 2004 are
not  necessarily  indicative of the results of operations to be expected for the
full fiscal year ending December 31, 2004.

(2) Stock-based Compensation

         Statement  of  Financial  Accounting  Standards  No. 123,  ("SFAS 123")
"Accounting for Stock-Based Compensation," encourages, but does not require, the
adoption of a fair  value-based  method of accounting  for employee  stock-based
compensation transactions. We have elected to apply the provisions of Accounting
Principles Board Opinion No. 25 ("Opinion 25"),  "Accounting for Stock Issued to
Employees,"  and  related  interpretations,   in  accounting  for  our  employee
stock-based  compensation plans. Under Opinion 25, compensation cost is measured
as the excess,  if any, of the quoted  market  price of our stock at the date of
the grant above the amount an employee must pay to acquire the stock.

         Had  compensation  costs for  options  granted  to our  employees  been
determined based on the fair value at the grant dates consistent with the method
proscribed  by SFAS No. 123,  our net income and  earnings  per share would have
been reduced to the pro forma amounts listed below:

                                                                          Three Months Ended
                                                                               March 31,
                                                                          2004             2003
                                                                     -------------    -------------
                                                                                
Pro forma impact of fair value method
 Net income available to common shareholders, as reported            $   1,865,817    $      86,873
 Pro-forma stock-based compensation costs under the fair value
  method, net of related tax                                               (10,000)          (7,683)
 Pro-forma income applicable to common shares under the
  fair-value method                                                      1,855,817           79,190
Earnings per common share
 Basic earnings per share reported                                            0.37             0.02
 Diluted earnings per share reported                                          0.36             0.02

 Pro-forma basic earnings per share under the fair value method               0.37             0.02

  Pro-forma diluted earnings per share under the fair value method            0.36             0.02




                                                                               4



Weighted average Black-Scholes fair value assumptions:
 Risk free rate                                                          4.0%-5.2%        4.0%-5.2%
 Expected life                                                            5-10 yrs         5-10 yrs
 Expected volatility                                                           44%            50.0%
 Expected dividend yield                                                      0.0%             0.0%



(3) Merger

         On January 1, 2004, we merged our subsidiaries, Rotary Gas Systems Inc,
NGE Leasing  Inc,  and Great Lakes  Compression  Inc.  with the parent  Company,
Natural Gas Services Group Inc. This had no effect on our consolidated financial
position or results of  operations,  with the exception of a small impact on our
state tax expenses.

(4)  Preferred Stock Conversion

         In accordance with the provisions of the Convertible Series A Preferred
Stock of Natural  Gas  Services  Group,  Inc.,  on March 26,  2004 each share of
Preferred  Stock  automatically  converted  to one  share of Common  Stock.  The
conversion  occurred after the closing market price of the stock was equal to or
higher than $6.50 for 20 consecutive trading days. 315,154 Preferred shares were
converted  at  that  time.   Dividends  payable  at  the  conversion  date  were
approximately $25,355.

(5) Earnings per common share

         The following table  reconciles the numerators and  denominators of the
basic and diluted earnings per share computation.

                                                         Three Months Ended
                                                               March 31,
                                                     --------------------------
                                                         2004           2003
                                                     -----------    -----------
Basic earnings per share Numerator:
  Net income                                         $ 1,893,739    $   117,883
  Less: dividends on preferred shares                    (27,922)       (31,010)
                                                     -----------    -----------
  Net income available to common shareholders        $ 1,865,817    $    86,873
                                                     ===========    ===========

 Denominator -
  Weighted average common shares outstanding           5,065,327      4,857,632
                                                     ===========    ===========

  Basic earnings per share                           $      0.37    $      0.02
                                                     ===========    ===========

Diluted earnings per share Numerator:
  Net income                                         $ 1,893,739    $   117,883
  Less: dividends on preferred shares (1)                (27,922)       (31,010)
                                                     -----------    -----------
  Net income available to common shareholders        $ 1,865,817    $    86,873
                                                     ===========    ===========



                                                                               5


 Denominator :
  Weighted average common shares outstanding           5,065,327      4,857,632
      Dilutive effect of common stock options
      and warrants                                       156,114        201,824
  Conversion of preferred shares (1)                        --             --
                                                     -----------    -----------
                                                       5,221,441      5,059,456
                                                     ===========    ===========

  Diluted earnings per share                         $      0.36    $      0.02
                                                     ===========    ===========

         (1)  Preferred  shares were  anti-dilutive  for the three  months ended
         March 31, 2004 and 2003

(6) Other Income

         On March 15, 2004 the President and C.E.O. of our company, Mr. Wayne L.
Vinson,  passed  away  after a  battle  with  cancer.  The  Company  held 2 life
insurance policies on him, 1 for $1,000,000 and 1 for $500,000, with the Company
as the  beneficiary.  At March 31, 2004,  the amounts were  recorded in Accounts
Receivable-other. The proceeds were received in April 2004.





























                                                                               6




Item 2.  Management's Discussion and Analysis, or Plan of Operation

Overview

         Our company provides  products and services to the oil and gas industry
and is engaged in (1) the manufacture,  service, sale, and rental of natural gas
compressors  to  enhance  the  productivity  of oil and gas  wells,  and (2) the
manufacture,  sale and rental of flares and flare ignition systems for plant and
production facilities. On January 1, 2004, we merged our subsidiaries into us.

Critical Accounting Policies and New Accounting Pronouncements

         See our December 31, 2003 Form 10-KSB for a discussion  of our critical
accounting  policies  and new  accounting  pronouncements.  There  have  been no
substantive changes since that time.

Liquidity and Capital Resources

         We have funded our operations  through public and private  offerings of
our common and preferred stock,  subordinated debt and bank debt.  Proceeds were
primarily  used to pay debt  and to fund  the  manufacture  and  fabrication  of
additional units for our rental fleet of natural gas compressors.

         At March 31, 2004, we had cash and cash  equivalents  of  approximately
$196,000, working capital of $1,281,000 and non-subordinated debt of $10,544,000
of which approximately $2,481,000 was classified as current. We had positive net
cash flow from operating activities of approximately $1,206,000 during the first
three months of 2004.  This was  primarily  from net income of  $1,894,000  plus
depreciation  and  amortization  of $527,000,  an increase in deferred  taxes of
$252,000, an increase in accounts payable and accrued liabilities of $1,213,000,
offset by an increase in accounts receivable-other of $1,500,000, an increase in
accounts  receivable-trade  of  $232,000,  a  decrease  in  deferred  income  of
$204,000, and an increase in inventory of $709,000.

         Our line of credit for $750,000  with interest at 1% over prime for one
year  expired  March 15, 2004 but was extended  until June 15, 2004.  Funds have
been drawn under the line of credit as of March 31, 2004 totaling $119,251.

         In accordance with the provisions of the Convertible Series A Preferred
Stock of Natural  Gas  Services  Group,  Inc.,  on March 26,  2004 each share of
Preferred  Stock  automatically  converted  to one  share of Common  Stock.  The
conversion  occurred after the closing market price of the stock was equal to or
higher than $6.50 for 20 consecutive trading days. 315,154 Preferred shares were
converted  at  that  time.   Dividends  payable  at  the  conversion  date  were
approximately  $25,355.  As a result the  conversion we will have a reduction in
expected  dividend  payments of  approximately  $75,000 for the remainder of the
year 2004.

         On  November  24,2003 we  completed  a new $10  million  senior  credit
facility with a $7 million  initial  borrowing  base.  The credit  facility is a
Multiple  Advance  Term  Promissory  Note  arranged  by Western  National  Bank,
Midland,  Texas.  The interest  rate is one percent over Wall Street prime rate.
Funds have been drawn under this line as of March 31, 2004 totaling $2,865,000.


Results of Operations

         Sales revenue from outside sources increased from $565,000 to $890,000,
or 58% for the three  months  ended March 31,  2004  compared to the same period
ended March 31, 2003.  This increase was mainly the result of an  improvement in
the sale of  compressors  and flare  units  compared to the same period in 2003.
Because our  products  are  custom-built,  fluctuations  in revenue from outside
sources is not unusual.




                                                                               7


                               [GRAPHIC OMITTED]

         Service and maintenance revenue increased from $377,000 to $424,000, or
12% for the three months ended March 31, 2004  compared to the same period ended
March 31, 2003.

         Leasing revenue increased from $1,401,000 to $2,255,000, or 61% for the
three  months  ended March 31, 2004  compared to the same period ended March 31,
2003. This increase was the result of additional  units added to our rental unit
fleet and  leased to third  parties.  The  company  ended the  quarter  with 444
compressor  packages in its rental fleet, up from 399 units at December 31, 2003
and 348 units at March 31, 2003.

                                [GRAPHIC OMITTED]

         The gross  margin  percentage  increased  from 52% for the three months
ended March 31,  2003,  to 57% for the same period  ended March 31,  2004.  This
improvement  resulted mainly from the relative  increase in leasing revenue as a
percentage  of the total  revenue.  Our  rental  fleet  carries  a gross  margin
averaging 70%, and increases in rented units improve our gross margin.
























                                                                               8


         Selling,  general and administrative expense increased from $519,000 to
$666,000 or 28% for the three months  ended March 31,  2003,  as compared to the
same period ended March 31, 2004.  This was mainly the result of the increase in
commissions  from  additional  leasing  contracts  on gas  compressors  to third
parties and legal expenses related to an internal investigation that was settled
in April 2004.

         Depreciation  and amortization  expense  increased 46% from $362,000 to
$527,000 for the three months ended March 31, 2003,  compared to the same period
ended March 31,  2004.  This  increase  was the result of 96 new gas  compressor
rental  units being added to rental  equipment  from March 31, 2003 to March 31,
2004.

         Other income  increased  approximately  $1,479,000 for the three months
ended March 31, 2004  compared to the same  period  ended March 31,  2003.  This
increase was due to the receipt of $1,500,000 in life  insurance  payable on Mr.
Wayne L. Vinson,  our former  President  and C.E.O.  His death on March 15, 2004
left the company as the  beneficiary  of two life  insurance  policies,  one for
$1,000,000,  and one for  $500,000.  These  amounts  were  recorded  as accounts
receivable-other at March 31, 2004 and were received in April 2004.

         There was a slight  increase in interest  expense for the three  months
ended March 31, 2004  compared to the same period ended March 31,  2003,  mainly
due to the new loan balances on vehicles and rental equipment.

         Provision for income tax increased $168,000,  or 200%, primarily due to
the increase in net taxable income.  The income from the life insurance proceeds
described above is not subject to federal income tax.


Item 3.  Controls and Procedures

(a) Evaluation of disclosure controls and procedures.

         Under the  supervision  and with the  participation  of our management,
including our chief executive officer and chief financial officer,  we evaluated
the  effectiveness  of the design and operation of our  disclosure  controls and
procedures  (as defined in Rule 13a-14(c)  under the Securities  Exchange Act of
1934) as of the end of the  period  covered  by this  report.  Based  upon  that
evaluation,  our chief executive  officer and chief financial  officer concluded
that,  as of the end of the  period  covered  by  this  report,  our  disclosure
controls and  procedures  are effective in timely  alerting them to the material
information  relating to us that are  required  to be  included in our  periodic
filings with the SEC.

(b) Changes in internal controls.

         There were no significant  changes made in our internal controls during
the period  covered by this report or, to our  knowledge,  in other factors that
could  significantly  affect  these  controls  subsequent  to the  date of their
evaluation.










                                                                               9


                           PART II - OTHER INFORMATION



NATURAL GAS SERVICES GROUP, INC.

Item 1.  Legal Proceedings

         From  time to  time,  we are a party  to  ordinary  routine  litigation
incidental  to our  business.  We are  not  currently  a  party  to any  pending
litigation, and we are not aware of any threatened litigation.

Item 5.  Other Information

         The  Nominating  Committee  of our Board of Directors  will  consider a
candidate for director  proposed by a  stockholder.  A candidate  must be highly
qualified  in terms of business  experience  and be both  willing and  expressly
interested in serving on the Board. A stockholder wishing to propose a candidate
for the  Committee's  consideration  should  forward  the  candidate's  name and
information about the candidate's  qualifications to Natural Gas Services Group,
Inc., Nominating Committee,  2911 South County Road 1260, Midland,  Texas 79706,
Attn.:  Charles  G.  Curtis,  Chairman.   Submissions  must  include  sufficient
biographical  information concerning the recommended individual,  including age,
employment history for at least the past five years indicating  employer's names
and description of the employer's business, educational background and any other
biographical  information  that would assist the  Committee in  determining  the
qualifications  of the individual.  The Committee will consider  recommendations
received  by a date not later than 120  calendar  days before the date our proxy
statement  was  released to  shareholders  in  connection  with the prior year's
annual  meeting  for  nomination  at that annual  meeting.  The  Committee  will
consider  nominations received beyond that date at the annual meeting subsequent
to the next annual meeting.

         The  Committee   evaluates   nominees  for  directors   recommended  by
stockholders  in the same  manner  in  which it  evaluates  other  nominees  for
directors. Minimum qualifications include the factors discussed above.


Item 6.  Exhibits and Reports on Form 8-K
(a)  Exhibits

Exhibit No.         Description
-----------         -----------

2.1                 Purchase   and  Sale   Agreement   by  and  between   Hy-Bon
                    Engineering Company, Inc. and NGE Leasing, Inc.(2)

3.1                 Articles of incorporation.(3)

3.2                 Amendment to articles of incorporation dated March 31, 1999,
                    and filed on May 25, 1999.(3)

3.3                 Amendment to articles of incorporation  dated July 25, 2001,
                    and filed on July 30, 2001.(3)

3.4                 Amendment to articles of incorporation  dated June 18, 2003,
                    and filed on June 19, 2003.(3)



                                                                              10


Exhibit No.         Description
-----------         -----------

3.5                 Articles  of  Merger  filed  on  December  30,  2003  to  be
                    effective  January 1, 2004  merging  NGE  Leasing,  Inc into
                    Natural Gas Services Group, Inc.(6)

3.6                 Articles  of  Merger  filed  on  December  30,  2003  to  be
                    effective  January 1, 2004 merging Rotary Gas Systems,  Inc.
                    into Natural Gas Services Group, Inc.(6)

3.7                 Articles  of  Merger  filed  on  December  30,  2003  to  be
                    effective  January 1, 2004 merging Great Lakes  Compression,
                    Inc. into Natural Gas Services Group, Inc.(6)

3.8                 Bylaws.(3)

4.1                 Form of warrant certificate.(3)

4.2                 Form of warrant agent agreement.(3)

4.3                 Form of lock-up agreement.(3)

4.4                 Form of  representative's  option for the purchase of common
                    stock.(3)

4.5                 Form  of   representative's   option  for  the  purchase  of
                    warrants.(3)

10.1                1998 Stock Option Plan.(3)

10.2                Asset Purchase  Agreement  between  Natural Gas  Acquisition
                    Corporation and Great Lakes Compression,  Inc. dated January
                    1, 2001.(3)

10.3                Amendment to Guaranty Agreement between Natural Gas Services
                    Group,  Inc.  and  Dominion  Michigan  Production  Services,
                    Inc.(3)

10.4                Form of Series A 10%  Subordinated  Notes due  December  31,
                    2006.(3)

10.5                Form of Five-Year Warrants to Purchase Common Stock.(3)

10.6                Warrants issued to Berry-Shino Securities, Inc.(3)

10.7                Warrants issued to Neidiger, Tucker, Bruner, Inc.(3)

10.8                Form of  warrant  issued  in  March  2001  for  guaranteeing
                    debt.(3)

10.9                Form of  warrant  issued  in  April  2002  for  guaranteeing
                    debt.(3)

10.10               Exhibits  3(c)(1),  3(c)(2),  3(c)(3),  3(1)(4),   13(d)(1),
                    13(d)(2) and 13(d)(3) to Asset  Purchase  Agreement  between
                    Natural  Gas   Acquisition   Corporation   and  Great  Lakes
                    Compression, Inc. dated January 1, 2001.(3)

10.11               Articles  of  Organization  of  Hy-Bon  Rotary  Compression,
                    L.L.C. dated April 17, 2000 and filed on April 20, 2001.(3)

10.12               Regulations of Hy-Bon Rotary Compression, L.L.C.(3)

10.13               First Amended and Restated Loan  Agreement  between  Natural
                    Gas Services Group, Inc. and Western National Bank(4)

10.14               Termination of Employment  Agreement  Letter relating to the
                    Employment Agreement of Alan Kurus(5)



                                                                              11


Exhibit No.         Description
-----------         -----------

10.15               Termination of Employment  Agreement  Letter relating to the
                    Employment Agreement of Wayne Vinson(5

10.16               Termination of Employment  Agreement  Letter relating to the
                    Employment Agreement of Earl R. Wait(5)

10.17               Lease  Agreement  dated  June  1,  2003  with  Steven  J.  &
                    Katherina L. Winer(6)

10.18               Lease  Agreement  dated June 19,  2003 with Wise  Commercial
                    Properties(6)

31.1                Certification of Chief Executive Officer required by Section
                    302 of the Sarbanes-Oxley Act of 2002. (1)

31.2                Certification of Chief Financial Officer required by Section
                    302 of the Sarbanes-Oxley Act of 2002. (1)

32.1                Certification  required by Section 906 of the Sarbanes-Oxley
                    Act of 2002. (1)

32.2                Certification  required by Section 906 of the Sarbanes-Oxley
                    Act of 2002. (1)
--------------------------------------------------------------------------------
(1)                 Filed herewith.
(2)                 Exhibit  2.1 is  incorporated  by  reference  to Exhibit 2.1
                    filed as an exhibit to our Current  Report on Form 8-K dated
                    February 28, 2003
(3)                 Exhibits   3.1  through  3.4  and  3.8  through   10.12  are
                    incorporated  by reference to the exhibits filed as exhibits
                    to our Registration Statement No. 333-88314
(4)                 Exhibit  10.13 is  incorporated  by reference to our Current
                    Report on Form 8-K filed on April 14, 2003
(5)                 Exhibits  10.14,   10.15  and  10.16  are   incorporated  by
                    reference to exhibits  10.25,  10.26 and 10.27 to our Annual
                    Report on Form 10-KSB for the year ended December 31, 2002
(6)                 Exhibits  3.5, 3.6,  10.17,  and 10.18 are  incorporated  by
                    reference to the same exhibits  filed with our Annual Report
                    on Form 10-KSB for the year ended December 31, 2003.


(b) Reports on Form 8-K

         On March  11,  2004,  under  Items 7 and 12 of Form  8-K,  we filed our
               earnings press release which announced our financial  results for
               the quarter and year ended December 31, 2003.

         On March 16,  2004,  under Item 5 of Form 8-K,  we  announced  that our
               President and Chief Executive  Officer,  Wayne L. Vinson,  passed
               away and that Wallace C.  Sparkman had been  appointed as interim
               Chief Executive Officer.






                                                                              12


SIGNATURES

         In accordance with the requirements of the Exchange Act, the registrant
caused this report to be signed on its behalf by the undersigned, thereunto duly
authorized.


NATURAL GAS SERVICES GROUP, INC.


By:  /s/ Wallace Sparkman
   -----------------------------
   Wallace Sparkman
   President and Chief Executive
   Officer

By:  /s/ Earl R. Wait
   -----------------------------
   Earl R. Wait
   Chief Financial Officer
    And Treasurer

May 12, 2004





















                                                                              13


                               INDEX TO EXHIBITS:

Exhibit No.         Description
-----------         -----------

2.1                 Purchase   and  Sale   Agreement   by  and  between   Hy-Bon
                    Engineering Company, Inc. and NGE Leasing, Inc.(2)

3.1                 Articles of incorporation.(3)

3.2                 Amendment to articles of incorporation dated March 31, 1999,
                    and filed on May 25, 1999.(3)

3.3                 Amendment to articles of incorporation  dated July 25, 2001,
                    and filed on July 30, 2001.(3)

3.4                 Amendment to articles of incorporation  dated June 18, 2003,

3.5                 Articles  of  Merger  filed  on  December  30,  2003  to  be
                    effective  January 1, 2004  merging  NGE  Leasing,  Inc into
                    Natural Gas Services Group, Inc.(6)

3.6                 Articles  of  Merger  filed  on  December  30,  2003  to  be
                    effective  January 1, 2004 merging Rotary Gas Systems,  Inc.
                    into Natural Gas Services Group, Inc.(6)

3.7                 Articles  of  Merger  filed  on  December  30,  2003  to  be
                    effective  January 1, 2004 merging Great Lakes  Compression,
                    Inc. into Natural Gas Services Group, Inc.(6)

3.8                 Bylaws.(3)

4.1                 Form of warrant certificate.(3)

4.2                 Form of warrant agent agreement.(3)

4.3                 Form of lock-up agreement.(3)

4.4                 Form of  representative's  option for the purchase of common
                    stock.(3)

4.5                 Form  of   representative's   option  for  the  purchase  of
                    warrants.(3)

10.1                1998 Stock Option Plan.(3)

10.2                Asset Purchase  Agreement  between  Natural Gas  Acquisition
                    Corporation and Great Lakes Compression,  Inc. dated January
                    1, 2001.(3)

10.3                Amendment to Guaranty Agreement between Natural Gas Services
                    Group,  Inc.  and  Dominion  Michigan  Production  Services,
                    Inc.(3)

10.4                Form of Series A 10%  Subordinated  Notes due  December  31,
                    2006.(3)

10.5                Form of Five-Year Warrants to Purchase Common Stock.(3)

10.6                Warrants issued to Berry-Shino Securities, Inc.(3)

10.7                Warrants issued to Neidiger, Tucker, Bruner, Inc.(3)

10.8                Form of  warrant  issued  in  March  2001  for  guaranteeing
                    debt.(3)

10.9                Form of  warrant  issued  in  April  2002  for  guaranteeing
                    debt.(3)



                                                                              14


Exhibit No.         Description
-----------         -----------

10.10               Exhibits  3(c)(1),  3(c)(2),  3(c)(3),  3(1)(4),   13(d)(1),
                    13(d)(2) and 13(d)(3) to Asset  Purchase  Agreement  between
                    Natural  Gas   Acquisition   Corporation   and  Great  Lakes
                    Compression, Inc. dated January 1, 2001.(3)

10.11               Articles  of  Organization  of  Hy-Bon  Rotary  Compression,
                    L.L.C. dated April 17, 2000 and filed on April 20, 2001.(3)

10.12               Regulations of Hy-Bon Rotary Compression, L.L.C.(3)

10.13               First Amended and Restated Loan  Agreement  between  Natural
                    Gas Services Group, Inc. and Western National Bank(4)

10.14               Termination of Employment  Agreement  Letter relating to the
                    Employment Agreement of Alan Kurus(5)



                                                                              11


Exhibit No.         Description
-----------         -----------

10.15               Termination of Employment  Agreement  Letter relating to the
                    Employment Agreement of Wayne Vinson(5

10.16               Termination of Employment  Agreement  Letter relating to the
                    Employment Agreement of Earl R. Wait(5)

10.17               Lease  Agreement  dated  June  1,  2003  with  Steven  J.  &
                    Katherina L. Winer(6)

10.18               Lease  Agreement  dated June 19,  2003 with Wise  Commercial
                    Properties(6)

31.1                Certification of Chief Executive Officer required by Section
                    302 of the Sarbanes-Oxley Act of 2002. (1)

31.2                Certification of Chief Financial Officer required by Section
                    302 of the Sarbanes-Oxley Act of 2002. (1)

32.1                Certification  required by Section 906 of the Sarbanes-Oxley
                    Act of 2002. (1)

32.2                Certification  required by Section 906 of the Sarbanes-Oxley
                    Act of 2002. (1)
--------------------------------------------------------------------------------
(1)                 Filed herewith.

(2)                 Exhibit  2.1 is  incorporated  by  reference  to Exhibit 2.1
                    filed as an exhibit to our Current  Report on Form 8-K dated
                    February 28, 2003

(3)                 Exhibits   3.1  through  3.4  and  3.8  through   10.12  are
                    incorporated  by reference to the exhibits filed as exhibits
                    to our Registration Statement No. 333-88314

(4)                 Exhibit  10.13 is  incorporated  by reference to our Current
                    Report on Form 8-K filed on April 14, 2003

(5)                 Exhibits  10.14,   10.15  and  10.16  are   incorporated  by
                    reference to exhibits  10.25,  10.26 and 10.27 to our Annual
                    Report on Form 10-KSB for the year ended December 31, 2002

(6)                 Exhibits  3.5, 3.6,  10.17,  and 10.18 are  incorporated  by
                    reference to the same exhibits  filed with our Annual Report
                    on Form 10-KSB for the year ended December 31, 2003.





                                                                              15