-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 VZJxp1a3O7u/KenYMlwR5QrF9uPJo0K8rgPp3PDdRbXlDzKRcy6c90dU6KaLGVw/
 VRagaGb1GyNzrJ18hFwIFw==

<SEC-DOCUMENT>0001374130-06-000002.txt : 20060830
<SEC-HEADER>0001374130-06-000002.hdr.sgml : 20060830
<ACCEPTANCE-DATETIME>20060830084539
ACCESSION NUMBER:		0001374130-06-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060828
FILED AS OF DATE:		20060830
DATE AS OF CHANGE:		20060830

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CHAPMAN BARRY
		CENTRAL INDEX KEY:			0001374130

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-05828
		FILM NUMBER:		061064038

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		610-208-2000

	MAIL ADDRESS:	
		STREET 1:		C/O CARPENTER TECHNOLOGY CORPORATION
		STREET 2:		PO BOX 14662
		CITY:			READING
		STATE:			PA
		ZIP:			19612

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:		1047 N PARK ROAD
		CITY:			WYOMISSING
		STATE:			PA
		ZIP:			19610-1339
		BUSINESS PHONE:		6102082000

	MAIL ADDRESS:	
		STREET 1:		1047 N PARK ROAD
		CITY:			WYOMISSING
		STATE:			PA
		ZIP:			19610
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-08-28</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001374130</rptOwnerCik>
            <rptOwnerName>CHAPMAN BARRY</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>CARPENTER TECHNOLOGY CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>PO BOX 14662</rptOwnerStreet2>
            <rptOwnerCity>READING</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19612</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP-Human Resources</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-08-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person was granted restricted stock under the Carpenter Technology Corporation Stock-Based Compensation Plan for Officers and Key Employees.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Barry J. Chapman</signatureName>
        <signatureDate>2006-08-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----