-----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,
 LDMWHRYAKrWetYIIrm67h2si9QuSiOali6xZiF9bhvZY8mAu8IKwILUBRU+jRNwX
 Jx7rLLMb1s/pzHRVwcsv5Q==

<SEC-DOCUMENT>0001444054-10-000008.txt : 20100527
<SEC-HEADER>0001444054-10-000008.hdr.sgml : 20100527
<ACCEPTANCE-DATETIME>20100527192631
ACCESSION NUMBER:		0001444054-10-000008
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100525
FILED AS OF DATE:		20100527
DATE AS OF CHANGE:		20100527

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Seeger Laureen
		CENTRAL INDEX KEY:			0001357325

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13252
		FILM NUMBER:		10864061

	MAIL ADDRESS:	
		STREET 1:		C/O MCKESSON CORPORATION
		STREET 2:		ONE POST STREET - 33RD FLOOR
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94104

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MCKESSON CORP
		CENTRAL INDEX KEY:			0000927653
		STANDARD INDUSTRIAL CLASSIFICATION:	WHOLESALE-DRUGS PROPRIETARIES & DRUGGISTS' SUNDRIES [5122]
		IRS NUMBER:				943207296
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		ONE POST ST
		STREET 2:		MCKESSON PLAZA
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94104
		BUSINESS PHONE:		4159838300

	MAIL ADDRESS:	
		STREET 1:		ONE POST ST
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94104

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MCKESSON HBOC INC
		DATE OF NAME CHANGE:	19990115

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MCKESSON CORP
		DATE OF NAME CHANGE:	19950209

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SP VENTURES INC
		DATE OF NAME CHANGE:	19940728
</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>2010-05-25</periodOfReport>

    <issuer>
        <issuerCik>0000927653</issuerCik>
        <issuerName>MCKESSON CORP</issuerName>
        <issuerTradingSymbol>MCK</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001357325</rptOwnerCik>
            <rptOwnerName>Seeger Laureen</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE POST STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94104</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP,Gen. Counsel &amp; Secretary</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-05-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>87480</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</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>87480</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>87480</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Options (Right-to-buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>67.81</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-05-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>91000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2017-05-25</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>91000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>91000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">These units vest 100% on 5/26/2013.</footnote>
        <footnote id="F2">This option granted 05/25/2010 vests 25% per year commencing on the first anniversary of the grant date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Donna Spinola, Attorney-in-fact</signatureName>
        <signatureDate>2010-05-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----