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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 RjLtCyv/JYmcm1w6RAS8gvy7AeNKrWJ2gqxNRLYxHWghhKef85N9o/qP9Y/4oWr0
 +xoHv5Ga3n9AMgbpAkJ//g==

<SEC-DOCUMENT>0000904454-08-000398.txt : 20080905
<SEC-HEADER>0000904454-08-000398.hdr.sgml : 20080905
<ACCEPTANCE-DATETIME>20080905173402
ACCESSION NUMBER:		0000904454-08-000398
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080822
FILED AS OF DATE:		20080905
DATE AS OF CHANGE:		20080905

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MEDASSETS INC
		CENTRAL INDEX KEY:			0001254419
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				510391128
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		100 NORTH POINT CENTER EAST
		STREET 2:		SUITE 200
		CITY:			ALPHARETTA
		STATE:			GA
		ZIP:			30022
		BUSINESS PHONE:		6783232500

	MAIL ADDRESS:	
		STREET 1:		100 NORTH POINT CENTER EAST
		STREET 2:		SUITE 200
		CITY:			ALPHARETTA
		STATE:			GA
		ZIP:			30022

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MACKESY D SCOTT
		CENTRAL INDEX KEY:			0001212997

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33881
		FILM NUMBER:		081059491

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		2128939500

	MAIL ADDRESS:	
		STREET 1:		320 PARK AVENUE STE 2500
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
</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>2008-08-22</periodOfReport>

    <issuer>
        <issuerCik>0001254419</issuerCik>
        <issuerName>MEDASSETS INC</issuerName>
        <issuerTradingSymbol>MDAS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001212997</rptOwnerCik>
            <rptOwnerName>MACKESY D SCOTT</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O WELSH, CARSON, ANDERSON &amp; STOWE</rptOwnerStreet1>
            <rptOwnerStreet2>320 PARK AVENUE, SUITE 2500</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>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-08-22</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>885</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6615</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F3"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock grant to non-employee directors of the Issuer.</footnote>
        <footnote id="F2">Vests over five months beginning on 8/1/08.</footnote>
        <footnote id="F3">The Reporting Person also indirectly beneficially owns 7,013,657 shares of Common Stock held by Welsh, Carson, Anderson &amp; Stowe IX, L.P.  The Reporting Person is a managing member of the sole general partner of Welsh, Carson, Anderson &amp; Stowe IX, L.P.  Pursuant to Instruction (4)(b)(iv) of Form 4, the Reporting Person has elected to report as indirectly beneficially owned the entire number of securities beneficially owned by such entity.  The Reporting Person disclaims beneficial ownership of any securities, and any proceeds thereof, that exceed his pecuniary interest therein and/or that are not actually distributed to him.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/David Mintz, Attorney-in-Fact</signatureName>
        <signatureDate>2008-09-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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