AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON JULY 7, 2005
                                                  REGISTRATION NO. 333-

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

                             ----------------------

                                    FORM S-8
                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933

                             ----------------------
                        ENGINEERED SUPPORT SYSTEMS, INC.
             (Exact name of registrant as specified in its charter)

               MISSOURI                                        43-1313242
    (State or other jurisdiction of                         (I.R.S. Employer
    incorporation or organization)                       Identification Number)

            201 EVANS LANE
         ST. LOUIS, MISSOURI                                      63121
(Address of principal executive offices)                       (Zip Code)

                             ----------------------

                        ENGINEERED SUPPORT SYSTEMS, INC.
                      2005 NON-EXECUTIVE STOCK OPTION PLAN

                             DAVID DOUGLASS MATTERN
                         SECRETARY AND GENERAL COUNSEL
                        ENGINEERED SUPPORT SYSTEMS, INC.
                                 201 EVANS LANE
                           ST. LOUIS, MISSOURI 63121
                    (Name and address of agent for service)
  Telephone number, including area code, of agent for service: (314) 553-4000

                             ----------------------
                                    Copy to:

                              THOMAS A. LITZ, ESQ
                              THOMPSON COBURN LLP
                              ONE U.S. BANK PLAZA
                           ST. LOUIS, MISSOURI 63101
                             PHONE: (314) 552-6000
                              FAX: (314) 552-7000


                                              CALCULATION OF REGISTRATION FEE

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                                                 Proposed Maximum           Proposed Maximum
 Title of Securities to     Amount to be        Offering Price Per         Aggregate Offering      Amount of Registration
     be Registered           Registered              Share(1)                   Price(1)                    Fee
---------------------------------------------------------------------------------------------------------------------------
                                                                                             
Common stock, $0.01 par
  value.................   600,000 shares(2)          $35.83                  $21,498,000                $2,530.32
===========================================================================================================================

(1)    Estimated solely for purposes of computing the Registration Fee
       pursuant to the provisions of Rule 457(h), based upon the average of
       the high and low sale prices of common stock, $0.01 par value, of the
       Registrant as reported on the Nasdaq National Market on July 1, 2005.

(2)    Reflects a three-for-two stock split paid in the form of a stock
       dividend distributed by the Registrant on April 15, 2005. Includes an
       indeterminate number of additional shares that may be issued to
       adjust the number of shares issued pursuant to the employee benefit
       plan described herein as the result of any future stock split, stock
       dividend or similar adjustment of Registrant's outstanding common
       stock.


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         The undersigned Registrant hereby files this Registration Statement
on Form S-8 (this "Registration Statement") to register 600,000 shares of
Engineered Support Systems, Inc. (the "Company") common stock, $0.01 par
value (the "Common Stock"), for issuance to participants under the
Engineered Support Systems, Inc. 2005 Non-Executive Stock Option Plan (the
"Plan").

                                   PART II

             INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Certain Documents by Reference.
         -----------------------------------------------

         The following documents filed with the Securities and Exchange
Commission are incorporated herein by reference:

         (a)      The Company's Annual Report on Form 10-K for the fiscal
                  year ended October 31, 2004, as amended by Amendment No. 1
                  to Annual Report on Form 10-K/A filed on February 1, 2005;

         (b)      The Company's Quarterly Reports on Form 10-Q for the
                  fiscal quarters ended January 31, 2005 and April 30, 2005;

         (c)      The Company's Current Reports on Form 8-K filed on January
                  11, 2005, February 2, 2005, February 7, 2005, February 11,
                  2005 as amended by Amendment No. 1 filed April 25, 2005
                  and Amendment No. 2 filed April 28, 2005, February 18,
                  2005 as amended by Amendment No. 1 filed February 22,
                  2005, March 4, 2005, April 6, 2005, April 14, 2005 as
                  amended by Amendment No. 1 filed May 6, 2005, April 25,
                  2005, April 28, 2005 and June 22, 2005; and

         (d)      The description of the Company's Common Stock as contained
                  in the Company's Registration Statement filed pursuant to
                  Section 12 of the Securities Exchange Act of 1934, as
                  amended, including any amendments or reports filed for the
                  purpose of updating such description.

         All documents filed by the Company pursuant to Sections 13(a),
13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended,
after the date of this Registration Statement and prior to the filing of a
post-effective amendment which indicates that all securities offered hereby
have been sold or which deregisters all securities remaining unsold, shall
be deemed to be incorporated by reference in this Registration Statement and
to be made a part hereof from the date of filing of such documents. Any
statements contained herein or in a document incorporated herein by
reference shall be deemed to be modified or superseded for purposes of this
Registration Statement to the extent that a statement contained herein or in
a subsequently filed document incorporated herein by reference modifies or
supersedes such document. Any statement so modified or superseded shall not
be deemed, except as so modified or superseded, to constitute a part of this
Registration Statement.

Item 4.  Description of Securities.
         -------------------------

         Not applicable.

Item 5.  Interests of Named Experts and Counsel.
         --------------------------------------

         Not applicable.

Item 6.  Indemnification of Directors and Officers.
         -----------------------------------------

         The By-Laws of the Company provide for indemnification of any
person who is or was a director,

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officer, employee or agent of the Company or serving at the request of the
Company as an officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, against expenses
actually and reasonably incurred by him in connection with any civil,
criminal, administrative or investigative action, suit, proceeding or claim
to the full extent and in the manner permitted by law. The Company also
maintains officers' and directors' liability insurance for the benefit of
its officers and directors.

         Section 351.355 of The General and Business Corporation Law of
Missouri provides that a corporation may indemnify any person who was or is
a party or is threatened to be made a party to any threatened, pending or
completed action, suit or proceeding by reason of the fact that he is or was
a director, officer, employee or agent of the corporation, or is or was
serving at the request of the corporation as a director, officer, employee
or agent of another corporation, partnership, joint venture, trust or other
enterprise, against expenses, including attorneys' fees, judgments, fines
and amounts paid in settlement actually and reasonably incurred by him in
connection with such action, suit or proceeding if he acted in good faith
and in a manner he reasonably believed to be in or not opposed to the best
interests of the corporation and, with respect to any criminal action or
proceeding, had no reasonable cause to believe his conduct was unlawful. In
the case of an action or suit by or in the right of the corporation, no
person shall be indemnified as to any claim, issue or matter as to which
such person shall have been adjudged to be liable for negligence or
misconduct in the performance of his duty to the corporation, unless and
only to the extent that the court in which the action or suit was brought
determines that such person is fairly and reasonably entitled to indemnity
for such expenses.

         Indemnification shall be made by a corporation only upon a
determination that the person to be indemnified has met the applicable
standard of conduct required. To the extent that a director, officer,
employee or agent of the corporation has been successful on the merits or
otherwise in the defense of any such action, suit or proceeding, he shall be
indemnified against expenses incurred in such defense.

         Expenses incurred in defense of any action, suit or proceeding may
be paid in advance of the final disposition upon receipt by the corporation
of a written undertaking by or on behalf of the person to repay such amount
if it is ultimately determined that the person is not entitled to
indemnification under the statute. The indemnification provided by statute
is not exclusive of any other rights to which such person may be entitled
under the articles of incorporation or by-laws, or any agreement, vote of
shareholders or disinterested directors or otherwise, and shall inure to the
benefit of the heirs, executors and administrators of such person.

Item 7.  Exemption From Registration Claimed.
         -----------------------------------

         Not applicable.

Item 8.  Exhibits.
         --------

         See Exhibit Index on page 7 hereof.

Item 9.  Undertakings.
         ------------

         (a)      The undersigned registrant hereby undertakes:

                  (1) To file, during any period in which offers and sales
         are being made, a post-effective amendment to this registration
         statement:

                  To include any material information with respect to the
         plan of distribution not previously disclosed in the registration
         statement or any material change to such information in the
         registration statement.

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                  (2) That, for the purpose of determining any liability
         under the Securities Act of 1933, each such post-effective
         amendment shall be deemed to be a new registration statement
         relating to the securities offered therein, and the offering of
         such securities at that time shall be deemed to be the initial bona
         fide offering thereof.

                  (3) To remove from registration by means of a
         post-effective amendment any of the securities being registered
         which remain unsold at the termination of the offering.

         (b)      The undersigned registrant hereby undertakes that, for
purposes of determining any liability under the Securities Act of 1933, each
filing of the registrant's annual report pursuant to Section 13(a) or
Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable,
each filing of an employee benefit plan's annual report pursuant to Section
15(d) of the Securities Exchange Act of 1934) that is incorporated by
reference in the registration statement shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial
bona fide offering thereof.

         (c)      Insofar as indemnification for liabilities arising under
the Securities Act of 1933 may be permitted to directors, officers and
controlling persons of the registrant pursuant to the foregoing provisions,
or otherwise, the registrant has been advised that in the opinion of the
Securities and Exchange Commission such indemnification is against public
policy as expressed in the Act and is, therefore, unenforceable. In the
event that a claim for indemnification against such liabilities (other than
the payment by the registrant of expenses incurred or paid by a director,
officer or controlling person of the registrant in the successful defense of
any action, suit or proceeding) is asserted by such director, officer or
controlling person in connection with the securities being registered, the
registrant will, unless in the opinion of its counsel the matter has been
settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against
public policy as expressed in the Act and will be governed by the final
adjudication of such issue.


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                                 SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
Registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-8 and has duly caused this
Registration Statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the County of St. Louis, State of Missouri, on
July 7, 2005.

                               ENGINEERED SUPPORT SYSTEMS, INC.


                               By    /s/ Gary C. Gerhardt
                                   -------------------------------------------
                                     Gary C. Gerhardt
                                     Vice Chairman and Chief Financial Officer

         KNOW ALL MEN BY THESE PRESENTS, that each person whose signature
appears below hereby constitutes and appoints Gary C. Gerhardt and David
Douglass Mattern, or either of them, his true and lawful attorney-in-fact
and agent, with full power of substitution and resubstitution, for him and
in his name, place and stead, in any and all capacities, to sign any and all
amendments (including, without limitation, post-effective amendments) to
this Registration Statement, and to file the same, with all exhibits
thereto, and other documents in connection therewith, with the Securities
and Exchange Commission, granting unto said attorney-in-fact and agent full
power and authority to do and perform each and every act and thing requisite
and necessary to be done in and about the premises, as fully to all intents
and purposes as he might or could do in person hereby ratifying and
confirming all that said attorneys-in-fact and agents or any of them, or
their or his substitute or substitutes, may lawfully do or cause to be done
by virtue hereof.

         Pursuant to the requirements of the Securities Act of 1933, as
amended, this Registration Statement has been signed below by the following
persons in the capacities and on the date indicated.



SIGNATURE                                                       TITLE                                      DATE
---------                                                       -----                                      ----
                                                                                                 
/s/ Gerald A. Potthoff                         Vice Chairman, Chief Executive Officer                  July 7, 2005
------------------------------------                        and Director
Gerald A. Potthoff                                  (principal executive officer)
Principal Executive Officer

/s/ Gary C. Gerhardt                           Vice Chairman, Chief Financial Officer                  July 7, 2005
------------------------------------                        and Director
Gary C. Gerhardt                                    (principal financial officer)
Principal Financial Officer

/s/ Steven J. Landmann                          Senior Vice President-Controller and                   July 7, 2005
------------------------------------                  Chief Accounting Officer
Steven J. Landmann                                 (principal accounting officer)
Principal Accounting Officer

/s/ Michael F. Shanahan, Sr.                           Nonexecutive Chairman
------------------------------------                        and Director                               July 7, 2005
Michael F. Shanahan, Sr.


                                                              Director                                 July 7, 2005
------------------------------------
Gregory P. Boyer

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SIGNATURE                                                       TITLE                                      DATE
---------                                                       -----                                      ----
                                                                                                 


/s/ William H. T. Bush                                        Director                                 July 7, 2005
------------------------------------
William H. T. Bush


                                                              Director                                 July 7, 2005
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Michael P. C. Carns


                                                              Director                                 July 7, 2005
------------------------------------
George E. Friel


/s/ Thomas J. Guilfoil                                        Director                                 July 7, 2005
------------------------------------
Thomas J. Guilfoil


/s/ S. Lee Kling                                              Director                                 July 7, 2005
------------------------------------
S. Lee Kling


/s/ Kenneth E. Lewi                                           Director                                 July 7, 2005
------------------------------------
Kenneth E. Lewi


                                                              Director                                 July 7, 2005
------------------------------------
Charles T. Robertson, Jr.


/s/ Crosbie E. Saint                                          Director                                 July 7, 2005
------------------------------------
Crosbie E. Saint


                                                              Director                                 July 7, 2005
------------------------------------
James A. Schaefer


/s/ Michael F. Shanahan, Jr.                                  Director                                 July 7, 2005
------------------------------------
Michael F. Shanahan, Jr.


/s/ Earl W. Wims                                              Director                                 July 7, 2005
------------------------------------
Earl W. Wims



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                                EXHIBIT INDEX
                                -------------

EXHIBIT NO.
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      5.1      Opinion of Thompson Coburn LLP as to the legality of the
               securities being registered.

      23.1     Consent of PricewaterhouseCoopers LLP.

      23.2     Consent of Thompson Coburn LLP (included in Exhibit 5.1).

      24.1     Power of Attorney (set forth on signature page hereto).

      99.1     Engineered Support Systems, Inc. 2005 Non-Executive Stock
               Option Plan.


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