-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 URCFwgDLrJdMM1vwjNGIcUbzfh45pr7sUjDw+gTpfE8a902r18rmC8g+BFD9BWZp
 LITh7JMZyNrBrRzO4iQ08Q==

<SEC-DOCUMENT>0001179110-09-002829.txt : 20090217
<SEC-HEADER>0001179110-09-002829.hdr.sgml : 20090216
<ACCEPTANCE-DATETIME>20090217165506
ACCESSION NUMBER:		0001179110-09-002829
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090113
FILED AS OF DATE:		20090217
DATE AS OF CHANGE:		20090217

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BEARD GRANT H
		CENTRAL INDEX KEY:			0001173731

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-10716
		FILM NUMBER:		09615009

	BUSINESS ADDRESS:	
		STREET 1:		47603 HALYARD DR
		CITY:			PLYMOUTH
		STATE:			MI
		ZIP:			48170
		BUSINESS PHONE:		7342076200

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TRIMAS CORP
		CENTRAL INDEX KEY:			0000842633
		STANDARD INDUSTRIAL CLASSIFICATION:	METAL FORGING & STAMPINGS [3460]
		IRS NUMBER:				382687639
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		39400 WOODWARD AVENUE, SUITE 130
		CITY:			BLOOMFIELD HILLS
		STATE:			MI
		ZIP:			48304
		BUSINESS PHONE:		2486315400

	MAIL ADDRESS:	
		STREET 1:		39400 WOODWARD AVENUE, SUITE 130
		CITY:			BLOOMFIELD HILLS
		STATE:			MI
		ZIP:			48304
</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>2009-01-13</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0000842633</issuerCik>
        <issuerName>TRIMAS CORP</issuerName>
        <issuerTradingSymbol>TRS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001173731</rptOwnerCik>
            <rptOwnerName>BEARD GRANT H</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>39400 WOODWARD AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 130</rptOwnerStreet2>
            <rptOwnerCity>BLOOMFIELD HILLS</rptOwnerCity>
            <rptOwnerState>MI</rptOwnerState>
            <rptOwnerZipCode>48304</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>former President and CEO</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-01-13</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>24318</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>166082</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">By the Beard Family Equities LLC, Grant H. Beard as Manager</footnote>
        <footnote id="F2">Prorated portion of restricted shares of common stock granted under the 2006 Long Term Equity Incentive Plan vested, with remainder forfeited pursuant to the terms of the Separation Agreement dated January 13, 2009.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Paula Reno attorney-in-fact</signatureName>
        <signatureDate>2009-02-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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