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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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 4nmO3Tiqrw21oLelGamuOQ==

<SEC-DOCUMENT>0001257503-10-000033.txt : 20100720
<SEC-HEADER>0001257503-10-000033.hdr.sgml : 20100720
<ACCEPTANCE-DATETIME>20100720144205
ACCESSION NUMBER:		0001257503-10-000033
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100720
FILED AS OF DATE:		20100720
DATE AS OF CHANGE:		20100720

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PREFORMED LINE PRODUCTS CO
		CENTRAL INDEX KEY:			0000080035
		STANDARD INDUSTRIAL CLASSIFICATION:	WATER, SEWER, PIPELINE, COMM AND POWER LINE CONSTRUCTION [1623]
		IRS NUMBER:				340676895
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		P.O. BOX 91129
		CITY:			CLEVELAND
		STATE:			OH
		ZIP:			44101

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			McKenna Dennis F
		CENTRAL INDEX KEY:			0001315040

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-31164
		FILM NUMBER:		10960256

	MAIL ADDRESS:	
		STREET 1:		P.O. BOX 91129
		CITY:			CLEVELAND
		STATE:			OH
		ZIP:			44101
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-07-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000080035</issuerCik>
        <issuerName>PREFORMED LINE PRODUCTS CO</issuerName>
        <issuerTradingSymbol>PLPC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001315040</rptOwnerCik>
            <rptOwnerName>McKenna Dennis F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>P.O. BOX 91129</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CLEVELAND</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44101</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>V.P. Global Business Dev.</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common shares, $2 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2010-07-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>28</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20033</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Employee stock option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>22.1</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2005-07-28</value>
            </exerciseDate>
            <expirationDate>
                <value>2014-07-27</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common shares, $2 par value</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">These restricted Common Shares granted to the Reporting Person represent the dividend on previously granted shares pursuant to the Company's Long Term Incentive Plan of 2008.  Provided that the Reporting Person has not voluntarily terminated his employment, 5 shares vest and will no longer be subject to risk of forfeiture on 8/29/2011, and depending on continued employment and on Company performance, 23 shares vest and will no longer be subject to risk of forfeiture on 12/31/2010.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/Eric R. Graef, by power of attorney</signatureName>
        <signatureDate>2010-07-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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