-----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,
 MPaMsOdCZdkgUwQ2SoXyuwIdBm/0hAtP3hBzRM9iIwJ7bOiVgK3bODXr0LQUM51r
 HpepGuqUhJ/sSW6OrBeqJQ==

<SEC-DOCUMENT>0001461136-10-000005.txt : 20101105
<SEC-HEADER>0001461136-10-000005.hdr.sgml : 20101105
<ACCEPTANCE-DATETIME>20101105135130
ACCESSION NUMBER:		0001461136-10-000005
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101104
FILED AS OF DATE:		20101105
DATE AS OF CHANGE:		20101105

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:			Igoe Paul Gerard
		CENTRAL INDEX KEY:			0001461136

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07665
		FILM NUMBER:		101167952

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		860.327.0202

	MAIL ADDRESS:	
		STREET 1:		LYDALL, INC.
		STREET 2:		ONE COLONIAL ROAD
		CITY:			MANCHESTER
		STATE:			CT
		ZIP:			06042
</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>2010-11-04</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001461136</rptOwnerCik>
            <rptOwnerName>Igoe Paul Gerard</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>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, Gen. Counsel &amp; Secretary</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>394</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>8.08</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17248</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">In conjunction with the vesting on November 4, 2010 of 1,250 shares of restricted stock from the restricted stock award granted on November 4, 2009, 394 shares of common stock were surrendered to satisfy tax obligations of the reporting person.</footnote>
        <footnote id="F2">Includes:  (i) 3,750 unvested shares subject to time-based restricted stock awards; (ii) 12,500 unvested shares subject to a performance-based restricted stock award; and (iii) 68 shares acquired by the reporting person under the Issuer's Employee Stock Purchase Plan since the filing of the last Form 4 by the reporting person on December 11, 2009.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Paul G. Igoe</signatureName>
        <signatureDate>2010-11-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----