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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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 zSaRUvHQ+ndCH/TKX6yWbw==

<SEC-DOCUMENT>0001111177-10-000006.txt : 20100819
<SEC-HEADER>0001111177-10-000006.hdr.sgml : 20100819
<ACCEPTANCE-DATETIME>20100819184544
ACCESSION NUMBER:		0001111177-10-000006
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100729
FILED AS OF DATE:		20100819
DATE AS OF CHANGE:		20100819

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CARPENTER TECHNOLOGY CORP
		CENTRAL INDEX KEY:			0000017843
		STANDARD INDUSTRIAL CLASSIFICATION:	STEEL WORKS, BLAST FURNACES  ROLLING MILLS (COKE OVENS) [3312]
		IRS NUMBER:				230458500
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		2 MERIDIAN BOULEVARD
		CITY:			WYOMISSING
		STATE:			PA
		ZIP:			19612
		BUSINESS PHONE:		6102082000

	MAIL ADDRESS:	
		STREET 1:		PO BOX 14662
		CITY:			READING
		STATE:			PA
		ZIP:			19612-4662

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SHOR MICHAEL L
		CENTRAL INDEX KEY:			0001111177

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-05828
		FILM NUMBER:		101028683

	MAIL ADDRESS:	
		STREET 1:		CARPENTER TECHNOLOGY CORPORATION
		STREET 2:		PO BOX 14662
		CITY:			READING
		STATE:			PA
		ZIP:			19612
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2010-07-29</periodOfReport>

    <dateOfOriginalSubmission>2010-08-02</dateOfOriginalSubmission>

    <issuer>
        <issuerCik>0000017843</issuerCik>
        <issuerName>CARPENTER TECHNOLOGY CORP</issuerName>
        <issuerTradingSymbol>CRS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001111177</rptOwnerCik>
            <rptOwnerName>SHOR MICHAEL L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>CARPENTER TECHNOLOGY CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>PO BOX 14662</rptOwnerStreet2>
            <rptOwnerCity>READING</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19612-4662</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr. VP-Engineered Products Op.</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-07-29</value>
                <footnoteId id="F1"/>
            </transactionDate>
            <deemedExecutionDate>
                <value>2010-06-30</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>16353</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>85255.68</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>786.38</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 401(k) Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Incorrect transaction date reported on original filing.</footnote>
        <footnote id="F2">The reporting person was granted restricted stock units under the Carpenter Technology Corporation Stock-Based Compensation Plan for Officers and Key Employees.</footnote>
        <footnote id="F3">Includes shares acquired under the Savings Plan of Carpenter Technology Corporation.  The share balance under the Savings Plan of Carpenter Technology fluctuates due to rounding differences produced by the Plan's method of estimating shares.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>K. Douglas Ralph/POA</signatureName>
        <signatureDate>2010-08-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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