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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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<SEC-DOCUMENT>0001343148-11-000027.txt : 20110217
<SEC-HEADER>0001343148-11-000027.hdr.sgml : 20110217
<ACCEPTANCE-DATETIME>20110217112926
ACCESSION NUMBER:		0001343148-11-000027
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110215
FILED AS OF DATE:		20110217
DATE AS OF CHANGE:		20110217

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MCDANIEL ROGER D
		CENTRAL INDEX KEY:			0001192788

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-32598
		FILM NUMBER:		11619851

	MAIL ADDRESS:	
		STREET 1:		C/O ENTEGRIS INC
		STREET 2:		3500 LYMAN BOULEVARD
		CITY:			CHASKA
		STATE:			MN
		ZIP:			55318

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ENTEGRIS INC
		CENTRAL INDEX KEY:			0001101302
		STANDARD INDUSTRIAL CLASSIFICATION:	PLASTICS PRODUCTS, NEC [3089]
		IRS NUMBER:				411941551
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		129 CONCORD ROAD
		CITY:			BILLERICA
		STATE:			MA
		ZIP:			01821
		BUSINESS PHONE:		9784366500

	MAIL ADDRESS:	
		STREET 1:		129 CONCORD ROAD
		CITY:			BILLERICA
		STATE:			MA
		ZIP:			01821
</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>2011-02-15</periodOfReport>

    <issuer>
        <issuerCik>0001101302</issuerCik>
        <issuerName>ENTEGRIS INC</issuerName>
        <issuerTradingSymbol>ENTG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001192788</rptOwnerCik>
            <rptOwnerName>MCDANIEL ROGER D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>63 AVENUE OF CHAMPIONS</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NICHOLASVILLE</rptOwnerCity>
            <rptOwnerState>KY</rptOwnerState>
            <rptOwnerZipCode>40356</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2011-02-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>9.491</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>77962</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares were sold pursuant to a Rule 10b5-1 Trading Plan established by the Reporting Person on February 10, 2010.</footnote>
        <footnote id="F2">The price reported in column 4 is a weighted average price reported in reliance on a letter from the Office of Chief Counsel, Securities and Exchange Commission's Division of Corporate Finance to the Society of Corporate Securities &amp; Corporate Governance Professionals dated June 25, 2008.  These shares were sold in multiple transactions at prices ranging from $9.4100 to $9.5900, inclusive.  The reporting person undertakes to provide Entegris, Inc. any shareholder of Entegris, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Peter W. Walcott, Attorney-In-Fact for Roger D. McDaniel</signatureName>
        <signatureDate>2011-02-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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