-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
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<SEC-DOCUMENT>0001140361-06-014764.txt : 20061023
<SEC-HEADER>0001140361-06-014764.hdr.sgml : 20061023
<ACCEPTANCE-DATETIME>20061023141824
ACCESSION NUMBER:		0001140361-06-014764
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20061017
FILED AS OF DATE:		20061023
DATE AS OF CHANGE:		20061023

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MILNER GRAHAM P
		CENTRAL INDEX KEY:			0001191646

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-06936
		FILM NUMBER:		061157436

	MAIL ADDRESS:	
		STREET 1:		228 WINTERHAWK LANE
		CITY:			ENCINITAS
		STATE:			CA
		ZIP:			92024

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			WD 40 CO
		CENTRAL INDEX KEY:			0000105132
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS CHEMICAL PRODUCTS [2890]
		IRS NUMBER:				951797918
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0831

	BUSINESS ADDRESS:	
		STREET 1:		1061 CUDAHY PL
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92110
		BUSINESS PHONE:		6192751400

	MAIL ADDRESS:	
		STREET 1:		1061 CUDAHY PLACE
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92110
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-10-17</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000105132</issuerCik>
        <issuerName>WD 40 CO</issuerName>
        <issuerTradingSymbol>WDFC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001191646</rptOwnerCik>
            <rptOwnerName>MILNER GRAHAM P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>228 WINTERHAWK LANE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ENCINITAS</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92024</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive Vice President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Non Qualified Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>35.99</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-10-17</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2007-10-17</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2016-10-17</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>10000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>96200</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">3400 exercisable 10/17/07, 3300 exercisable 10/17/08, 3300 exercisable 10/17/09.</footnote>
        <footnote id="F2">Incentive Stock Option (ISO) 6000 shares exercisable 01/01/00 at $31.75 exp. 09/22/07; ISO 6000 shares exercisable 01/01/01 at $23.063 exp. 09/29/08; Non Qualified Stock Options (NQSO) 10000 shares exercisable 09/28/00 at $23.50 exp. 09/28/09; NQSO 2104 shares exercisable 09/26/01 at $20.813 exp. 09/26/10; ISO 15096 shares exercisable 09/26/01 at $20.813 exp. 09/26/10; NQSO 5181 shares exercisable 09/25/02 at $20.75 exp. 09/25/11; ISO 4819 shares exercisable 09/25/02 at $20.75 exp. 09/25/11; NQSO 10000 shares exercisable 9/24/03 at $27.56 exp. 09/24/12; NQSO 10000 shares (3400 exercisable 09/23/04; 3300 exercisable 09/23/05; 3300 exercisable 09/23/06) at $29.30 exp. 09/24/13; NQSO 8000 shares (2720 exercisable 10/19/05; 2640 exercisable 10/19/06; 2640 exercisable 10/19/07) at $27.67 exp. 10/19/14; NQSO 9000 shares (3060 exercisable 10/18/06, 2970 exercisable 10/18/07, 2970 exercisable 10/18/08) at $27.27 exp. 10/18/15.</footnote>
        <footnote id="F3">In addition to the the shares owned in the above footnote:  NQSO 10000 shares (3400 exercisable 10/17/07, 3300 exercisable 10/17/08 3400 exercisable 10/17/09) at $35.99.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Graham P Milner</signatureName>
        <signatureDate>2006-10-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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