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

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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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