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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 M3DiAqLkKGcVW1xBz486ruo/O72zlfZCOF4y3oOLRigm/Z0u993jNfbQ8HUA41qP
 aM2Yf5JxzKUzI9kKUiNkoA==

<SEC-DOCUMENT>0001179110-03-005751.txt : 20030815
<SEC-HEADER>0001179110-03-005751.hdr.sgml : 20030815
<ACCEPTANCE-DATETIME>20030815160609
ACCESSION NUMBER:		0001179110-03-005751
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030813
FILED AS OF DATE:		20030815

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ECOLAB INC
		CENTRAL INDEX KEY:			0000031462
		STANDARD INDUSTRIAL CLASSIFICATION:	SOAP, DETERGENT, CLEANING PREPARATIONS, PERFUMES, COSMETICS [2840]
		IRS NUMBER:				410231510
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ECOLAB CTR
		STREET 2:		370 WABASHA ST NORTH
		CITY:			ST PAUL
		STATE:			MN
		ZIP:			55102
		BUSINESS PHONE:		6512932233

	MAIL ADDRESS:	
		STREET 1:		370 WABASHA ST NORTH
		CITY:			ST. PAUL
		STATE:			MN
		ZIP:			55102

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ECONOMICS LABORATORY INC
		DATE OF NAME CHANGE:	19861203

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FRITZE STEVEN L
		CENTRAL INDEX KEY:			0001198756

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09328
		FILM NUMBER:		03850870

	BUSINESS ADDRESS:	
		STREET 1:		370 WABASHA ST NORTH
		CITY:			ST PAUL
		STATE:			MN
		ZIP:			55102
		BUSINESS PHONE:		6512932051

	MAIL ADDRESS:	
		STREET 1:		370 WBASHA ST NORTH
		CITY:			ST PAUL
		STATE:			MN
		ZIP:			55102
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>
<periodOfReport>2003-08-13</periodOfReport>
<notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0000031462</issuerCik>
        <issuerName>ECOLAB INC</issuerName>
        <issuerTradingSymbol>ECL</issuerTradingSymbol>
</issuer>
<reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001198756</rptOwnerCik>
            <rptOwnerName>FRITZE STEVEN L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ECOLAB INC.</rptOwnerStreet1>
            <rptOwnerStreet2>370 WABASHA STREET N.</rptOwnerStreet2>
            <rptOwnerCity>ST. PAUL</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55102</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector>
<isOfficer>1</isOfficer>
<isTenPercentOwner>0</isTenPercentOwner>
<isOther>0</isOther>
<officerTitle>Senior Vice President &amp; CFO</officerTitle>
<otherText></otherText>
</reportingOwnerRelationship>
</reportingOwner>
<nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock</value>
</securityTitle>
<transactionDate><value>2003-08-13</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>F</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>393</value>
<footnoteId id="F1"></footnoteId>
</transactionShares>
<transactionPricePerShare><value>25.26</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>D</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>1655</value>
<footnoteId id="F2"></footnoteId>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeHolding><securityTitle><value>Common Stock</value>
</securityTitle>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>10800.849</value>
<footnoteId id="F3"></footnoteId>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership><value>By Ecolab Savings Plan</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeHolding>
</nonDerivativeTable>
<derivativeTable></derivativeTable>
<footnotes><footnote id="F1">Reflects the reporting person's withholding of shares from the vesting of a restricted stock award to satisfy withholding taxes in accordance with Rule 16b-3.</footnote>
<footnote id="F2">The number of shares reported by the reporting person have been doubled to reflect the 2 for 1 stock split of Ecolab Inc. Common Stock effected in the form of 100% stock dividend on June 6, 2003.</footnote>
<footnote id="F3">Number of UNITS owned by the reporting person in the Ecolab Stock Fund of the Ecolab Savings Plan (401(k) Plan) as of July 31, 2003.  Includes 31.122 UNITS acquired since the reporting person's last report. (The 10,800.849 UNITS are the equivalent of approximately 20,286.01 SHARES of the issuer's Common Stock.)</footnote>
</footnotes>
<ownerSignature><signatureName>/s/David F. Duvick, as Attorney-in-Fact for Steve L. Fritze</signatureName>
<signatureDate>2003-08-15</signatureDate>
</ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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