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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0000099780-10-000006.txt : 20100105
<SEC-HEADER>0000099780-10-000006.hdr.sgml : 20100105
<ACCEPTANCE-DATETIME>20100105144035
ACCESSION NUMBER:		0000099780-10-000006
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100104
FILED AS OF DATE:		20100105
DATE AS OF CHANGE:		20100105

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GAFFORD RONALD J
		CENTRAL INDEX KEY:			0001222591

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06903
		FILM NUMBER:		10506022

	MAIL ADDRESS:	
		STREET 1:		TRINITY INDUSTRIES INC
		STREET 2:		2525 STEMMONS FREEWAY
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75207

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TRINITY INDUSTRIES INC
		CENTRAL INDEX KEY:			0000099780
		STANDARD INDUSTRIAL CLASSIFICATION:	RAILROAD EQUIPMENT [3743]
		IRS NUMBER:				750225040
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2525 STEMMONS FREEWAY
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75207-2401
		BUSINESS PHONE:		214-631-4420

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	TRINITY STEEL CO INC
		DATE OF NAME CHANGE:	19720407
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-01-04</periodOfReport>

    <issuer>
        <issuerCik>0000099780</issuerCik>
        <issuerName>TRINITY INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>NYSE/TRN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001222591</rptOwnerCik>
            <rptOwnerName>GAFFORD RONALD J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2525 STEMMONS FREEWAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75207</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Trinity Phantom Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-01-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1148</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>18.05</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1148</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>16308</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Trinity Phantom Stock Units were accrued under the Trinity Industries, Inc. Deferred Plan for Directors Fees.  Stock units are converted at &quot;1 - for - 1&quot; (a rate of one stock unit per one share of Trinity common stock).  Settlement of the account will be in cash after the reporting person's retirement.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Mary E. Henderson For:  Ronald J. Gafford</signatureName>
        <signatureDate>2010-01-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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