Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
LEWIS DIANA D
  2. Issuer Name and Ticker or Trading Symbol
ECOLAB INC [ECL]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP - Human Resources
(Last)
(First)
(Middle)
ECOLAB INC., 370 WABASHA STREET N.
3. Date of Earliest Transaction (Month/Day/Year)
09/14/2005
(Street)

ST. PAUL, MN 55102
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 09/14/2005   M   52,000 A $ 19.265 125,483.704 D  
Common Stock 09/14/2005   F(1)   39,721 D $ 32.77 85,762.704 D  
Common Stock 09/14/2005   M   32,000 A $ 18.96 117,762.704 D  
Common Stock 09/14/2005   F(1)   24,272 D $ 32.77 93,490.704 D  
Common Stock               11,508.504 (2) I By the Ecolab Savings Plan

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (Right to Buy) (3) $ 19.265 (3) 09/14/2005   M     52,000 (3) 08/18/2001(3) 08/18/2010 Common Stock 52,000 $ 0 0 D  
Employee Stock Option (Right to Buy) (4) $ 18.96 (4) 09/14/2005   M     32,000 (4) 12/06/2002(4) 12/06/2011 Common Stock 32,000 $ 0 20,000 D  
Employee Stock Option (Right to Buy) $ 32.77 09/14/2005   A   39,721   09/14/2005 08/18/2010 Common Stock 39,721 $ 0 39,721 D  
Employee Stock Option (Right to Buy) $ 32.77 09/14/2005   A   24,272   09/14/2005 12/06/2011 Common Stock 24,272 $ 0 24,272 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
LEWIS DIANA D
ECOLAB INC.
370 WABASHA STREET N.
ST. PAUL, MN 55102
      SVP - Human Resources  

Signatures

 /s/David F. Duvick, Attorney-in-Fact for Diana D. Lewis   09/15/2005
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Reflects the reporting person's payment of the exercise price and withholding taxes for a stock option issued in accordance with Rule 16b-3 by delivering or withholding shares of Ecolab Common Stock.
(2) The reporting person indirectly holds 11,508.504 UNITS in the Ecolab Stock Fund of the Ecolab Savings Plan (401(k) Plan) as of August 31, 2005, including 31.107 units acquired since the reporting person's last report. (The 11,508.504 units are the equivalent to approximately 21,703 shares of the issuer's Common Stock.)
(3) Option granted under the Ecolab Inc. 1997 Stock Incentive Plan on August 18, 2000. The option was originally reported as covering 26,000 shares at an exercise price of $38.53125 but has been adjusted to reflect a stock split on June 6, 2003. The option became exercisable, cumulatively, as to one-third of the total shares subject to the option on each of the first and second anniversaries of the date of grant and as to the remaining shares on the third anniversary of the date of grant.
(4) Option granted under the Ecolab Inc. 1997 Stock Incentive Plan on December 6, 2001. The option was originally reported as covering 26,000 shares at an exercise price of $37.92 but has been adjusted to reflect a stock split on June 6, 2003. The option became exercisable, cumulatively, as to one-third of the total shares subject to the option on each of the first and second anniversaries of the date of grant and as to the remaining shares on the third anniversary of the date of grant.

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