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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 Aaj580rKmx2FuvtDWJR9CD8udsdaLV2KGmGKbKADnhyQ0tKYFs4+TeX4oceKoQj5
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<SEC-DOCUMENT>0001179110-10-007649.txt : 20100430
<SEC-HEADER>0001179110-10-007649.hdr.sgml : 20100430
<ACCEPTANCE-DATETIME>20100430184104
ACCESSION NUMBER:		0001179110-10-007649
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100428
FILED AS OF DATE:		20100430
DATE AS OF CHANGE:		20100430

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Mulligan Donal L
		CENTRAL INDEX KEY:			0001406019

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-16191
		FILM NUMBER:		10789293

	MAIL ADDRESS:	
		STREET 1:		ONE GENERAL MILLS BLVD
		CITY:			MINNEAPOLIS
		STATE:			MN
		ZIP:			55426

	FORMER NAME:	
		FORMER CONFORMED NAME:	Mulligan Donal
		DATE OF NAME CHANGE:	20070710

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TENNANT CO
		CENTRAL INDEX KEY:			0000097134
		STANDARD INDUSTRIAL CLASSIFICATION:	REFRIGERATION & SERVICE INDUSTRY MACHINERY [3580]
		IRS NUMBER:				410572550
		STATE OF INCORPORATION:			MN
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		701 N LILAC DR
		STREET 2:		PO BOX 1452
		CITY:			MINNEAPOLIS
		STATE:			MN
		ZIP:			55440
		BUSINESS PHONE:		6125401200

	MAIL ADDRESS:	
		STREET 1:		701 N LILAC DR
		STREET 2:		PO BOX 1452
		CITY:			MINNEAPOLIS
		STATE:			MN
		ZIP:			55440

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	TENNANT G H CO
		DATE OF NAME CHANGE:	19700515
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-04-28</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000097134</issuerCik>
        <issuerName>TENNANT CO</issuerName>
        <issuerTradingSymbol>TNC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001406019</rptOwnerCik>
            <rptOwnerName>Mulligan Donal L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE GENERAL MILLS BLVD. WO5A-2</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>GOLDEN VALLEY</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55426</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-04-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>875</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1422</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>34.28</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-04-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2256</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2020-04-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2256</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2256</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Non-Employee Director Restricted Stock Grant.</footnote>
        <footnote id="F2">The option is exercisable in one-third increments on each of April 28, 2011, April 28, 2012 and April 28, 2013.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Amy C. Seidel on behalf of Donal L. Mulligan</signatureName>
        <signatureDate>2010-04-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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