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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 F+HLpinyWRdE9WOvaip13RC12n5RKU6XAdIDTADidEIFhJ0PfPnfu3LNV340aRPW
 7z2sHtGi0ndXIBDOEGUL4A==

<SEC-DOCUMENT>0000921895-08-002240.txt : 20080819
<SEC-HEADER>0000921895-08-002240.hdr.sgml : 20080819
<ACCEPTANCE-DATETIME>20080819172558
ACCESSION NUMBER:		0000921895-08-002240
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080815
FILED AS OF DATE:		20080819
DATE AS OF CHANGE:		20080819

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GENCORP INC
		CENTRAL INDEX KEY:			0000040888
		STANDARD INDUSTRIAL CLASSIFICATION:	FABRICATED RUBBER PRODUCTS, NEC [3060]
		IRS NUMBER:				340244000
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1130

	BUSINESS ADDRESS:	
		STREET 1:		HIGHWAY 50 & AEROJET ROAD
		CITY:			RANCHO CORDOVA
		STATE:			CA
		ZIP:			95670
		BUSINESS PHONE:		9163554000

	MAIL ADDRESS:	
		STREET 1:		HIGHWAY 50 & AEROJET ROAD
		CITY:			RANCHO CORDOVA
		STATE:			CA
		ZIP:			95670

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	GENERAL TIRE & RUBBER CO
		DATE OF NAME CHANGE:	19840330

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LICHTENSTEIN WARREN G
		CENTRAL INDEX KEY:			0001005784
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-01520
		FILM NUMBER:		081028511

	BUSINESS ADDRESS:	
		STREET 1:		C/O STEEL PARTNERS L P
		STREET 2:		32ND FLOOR 590 MADISON AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
		BUSINESS PHONE:		212-758-3232

	MAIL ADDRESS:	
		STREET 1:		C/O STEEL PARTNERS II L P
		STREET 2:		590 MADISON AVENUE, 32ND FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>lic43.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-08-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000040888</issuerCik>
        <issuerName>GENCORP INC</issuerName>
        <issuerTradingSymbol>GY</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001005784</rptOwnerCik>
            <rptOwnerName>LICHTENSTEIN WARREN G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O STEEL PARTNERS II, L.P.</rptOwnerStreet1>
            <rptOwnerStreet2>590 MADISON AVENUE, 32ND FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Appreciation Right</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>8.4800</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-08-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>12000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2009-02-15</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-08-15</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, Par Value $0.10</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>12000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Appreciation Right</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>8.4800</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-08-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2009-03-25</value>
            </exerciseDate>
            <expirationDate>
                <value>2018-08-15</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, Par Value $0.10</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>6000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Stock Appreciation Right vests in 50% increments on 2/15/09 and 8/15/09.</footnote>
        <footnote id="F2">The Reporting Person is a member of a Section 13(d) group that owns more than 10% of the Issuer's outstanding common stock. As the manager of Steel Partners LLC and the managing member of Steel Partners II GP LLC, the investment manager and general partner of Steel Partners II, L.P., respectively, Mr. Lichtenstein may be deemed to beneficially own an additional 8,034,059 shares owned by Steel Partners II, L.P., representing 14.0% of the Issuer's outstanding shares. Mr. Lichtenstein disclaims beneficial ownership of such shares except to the extent of his pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: /s/ Sanford Antignas, as Attorney in Fact for Warren G. Lichtenstein</signatureName>
        <signatureDate>2008-08-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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