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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 C9+Iw5xH9/AKrUEwlf1CO0B/GNf2cxXa68TIZCCtU9POP5w7lLp/YXvZ4s+JBnNX
 Q0i24KMzRcy9Kp+URQ1NXQ==

<SEC-DOCUMENT>0000737875-09-000022.txt : 20090804
<SEC-HEADER>0000737875-09-000022.hdr.sgml : 20090804
<ACCEPTANCE-DATETIME>20090804125108
ACCESSION NUMBER:		0000737875-09-000022
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090804
FILED AS OF DATE:		20090804
DATE AS OF CHANGE:		20090804

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Gerlach John G
		CENTRAL INDEX KEY:			0001415708

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-21344
		FILM NUMBER:		09982708

	MAIL ADDRESS:	
		STREET 1:		32 WYNDHAM HILLS
		CITY:			CRESCO
		STATE:			PA
		ZIP:			18326

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FIRST KEYSTONE CORP
		CENTRAL INDEX KEY:			0000737875
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				232249083
		STATE OF INCORPORATION:			PA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		111 W FRONT ST
		CITY:			BERWICK
		STATE:			PA
		ZIP:			18603
		BUSINESS PHONE:		570-752-3671 EXT 173

	MAIL ADDRESS:	
		STREET 1:		111 WEST FRONT STREET
		CITY:			BERWICK
</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>2009-08-04</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000737875</issuerCik>
        <issuerName>FIRST KEYSTONE CORP</issuerName>
        <issuerTradingSymbol>fkys.ob</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001415708</rptOwnerCik>
            <rptOwnerName>Gerlach John G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>32 WYNDHAM HILLS</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CRESCO</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>18326</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>First Keystone Corporation Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-08-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>543</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>16</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7932</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>John G. Gerlach</signatureName>
        <signatureDate>2009-08-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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