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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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 QCM+Gs3IwltmkVzIMrsSvA==

<SEC-DOCUMENT>0001472668-10-000002.txt : 20100701
<SEC-HEADER>0001472668-10-000002.hdr.sgml : 20100701
<ACCEPTANCE-DATETIME>20100701122935
ACCESSION NUMBER:		0001472668-10-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100630
FILED AS OF DATE:		20100701
DATE AS OF CHANGE:		20100701

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DUFFY W LESLIE
		CENTRAL INDEX KEY:			0001227816

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07665
		FILM NUMBER:		10929799

	MAIL ADDRESS:	
		STREET 1:		C/O CAHILL GORDON & REINDEL
		STREET 2:		80 PINE STREET 19TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10005

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
</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>0001227816</rptOwnerCik>
            <rptOwnerName>DUFFY W LESLIE</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>44562</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 W. Leslie Duffy</signatureName>
        <signatureDate>2010-07-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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