<SEC-DOCUMENT>0001127602-11-013816.txt : 20110427
<SEC-HEADER>0001127602-11-013816.hdr.sgml : 20110427
<ACCEPTANCE-DATETIME>20110427142841
ACCESSION NUMBER:		0001127602-11-013816
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110426
FILED AS OF DATE:		20110427
DATE AS OF CHANGE:		20110427

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ZIMMER DAVID R
		CENTRAL INDEX KEY:			0001227478

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07635
		FILM NUMBER:		11783110

	MAIL ADDRESS:	
		STREET 1:		1255 INDIAN MOUND WEST
		CITY:			BLOOMFIELD
		STATE:			MI
		ZIP:			48301

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TWIN DISC INC
		CENTRAL INDEX KEY:			0000100378
		STANDARD INDUSTRIAL CLASSIFICATION:	GENERAL INDUSTRIAL MACHINERY & EQUIPMENT [3560]
		IRS NUMBER:				390667110
		STATE OF INCORPORATION:			WI
		FISCAL YEAR END:			0119

	BUSINESS ADDRESS:	
		STREET 1:		1328 RACINE ST
		CITY:			RACINE
		STATE:			WI
		ZIP:			53403
		BUSINESS PHONE:		2626384000

	MAIL ADDRESS:	
		STREET 1:		1328 RACINE STREET
		CITY:			RACINE
		STATE:			WI
		ZIP:			53403

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	TWIN DISC CLUTCH CO
		DATE OF NAME CHANGE:	19770217
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>PRIMARY DOCUMENT
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    <periodOfReport>2011-04-26</periodOfReport>

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        <issuerName>TWIN DISC INC</issuerName>
        <issuerTradingSymbol>TWIN</issuerTradingSymbol>
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            <rptOwnerName>ZIMMER DAVID R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>STONEBRIDGE BUSINESS PARTNERS</rptOwnerStreet1>
            <rptOwnerStreet2>101 W. BIG BEAVER, SUITE 1400</rptOwnerStreet2>
            <rptOwnerCity>TROY</rptOwnerCity>
            <rptOwnerState>MI</rptOwnerState>
            <rptOwnerZipCode>48084</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
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                <transactionShares>
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    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>/s/ David R. Zimmer</signatureName>
        <signatureDate>2011-04-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
