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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 BCvuGzc/pPfazBx4czLg/AGWrv/83P2IF6XtmGvHIS1cV4K1AIe3BWtCUu8jisPo
 4nlJfxragiYY5Eh7YraM5g==

<SEC-DOCUMENT>0001472668-10-000005.txt : 20100701
<SEC-HEADER>0001472668-10-000005.hdr.sgml : 20100701
<ACCEPTANCE-DATETIME>20100701123349
ACCESSION NUMBER:		0001472668-10-000005
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100630
FILED AS OF DATE:		20100701
DATE AS OF CHANGE:		20100701

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LYDALL INC /DE/
		CENTRAL INDEX KEY:			0000060977
		STANDARD INDUSTRIAL CLASSIFICATION:	MOTOR VEHICLE PARTS & ACCESSORIES [3714]
		IRS NUMBER:				060865505
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE COLONIAL RD
		STREET 2:		P O BOX 151
		CITY:			MANCHESTER
		STATE:			CT
		ZIP:			06045-0151
		BUSINESS PHONE:		2036461233

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	COLONIAL BOARD CO
		DATE OF NAME CHANGE:	19700115

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GURLEY WILLIAM D
		CENTRAL INDEX KEY:			0001355571

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07665
		FILM NUMBER:		10929817

	MAIL ADDRESS:	
		STREET 1:		C/O LYDALL, INC.
		STREET 2:		1 COLONIAL ROAD PO BOX 151
		CITY:			MANCHESTER
		STATE:			CT
		ZIP:			06040
</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>2010-06-30</periodOfReport>

    <issuer>
        <issuerCik>0000060977</issuerCik>
        <issuerName>LYDALL INC /DE/</issuerName>
        <issuerTradingSymbol>LDL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001355571</rptOwnerCik>
            <rptOwnerName>GURLEY WILLIAM D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O LYDALL, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>ONE COLONIAL ROAD</rptOwnerStreet2>
            <rptOwnerCity>MANCHESTER</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06042</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>2010-06-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2357</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>7.64</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>31549</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Pursuant to the Issuer's Amended and Restated 2003 Stock Incentive Compensation Plan, on June 30 and December 31 of each year during the term of the Plan, non-employee Directors of the Company automatically receive a fully vested and unrestricted stock award consisting of that number of whole shares of common stock equal in value to 50% of their Annual Cash Retainer Amount, based on the fair market value of the Issuer's common stock as of the close of business on such dates and in lieu of any Annual Cash Retainer.  The 2010 Annual Cash Retainer Amount for non-employee Directors is $36,000; accordingly, each non-employee Director received $18,000 worth of the Issuer's common stock on June 30, 2010.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Paul G. Igoe, Attorney-in-fact for William D. Gurley</signatureName>
        <signatureDate>2010-07-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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