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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,
 M2dFm0KiXgFoPmFm3ziO5MpAFHaSVYetrEF8kMj7Wkl956s21bK3kYcfnNFqDmIY
 HJV9xNpafvemNDcqG3y/RA==

<SEC-DOCUMENT>0000905729-05-000279.txt : 20050805
<SEC-HEADER>0000905729-05-000279.hdr.sgml : 20050805
<ACCEPTANCE-DATETIME>20050805140928
ACCESSION NUMBER:		0000905729-05-000279
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050803
FILED AS OF DATE:		20050805
DATE AS OF CHANGE:		20050805

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CHEMICAL FINANCIAL CORP
		CENTRAL INDEX KEY:			0000019612
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				382022454
		STATE OF INCORPORATION:			MI
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		333 E MAIN ST
		CITY:			MIDLAND
		STATE:			MI
		ZIP:			48640
		BUSINESS PHONE:		5176313310

	MAIL ADDRESS:	
		STREET 1:		333 E MAIN ST
		CITY:			MIDLAND
		STATE:			MI
		ZIP:			48640

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			REISNER JOHN A
		CENTRAL INDEX KEY:			0001213664

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-08185
		FILM NUMBER:		051002110

	MAIL ADDRESS:	
		STREET 1:		333 E MAIN ST
		CITY:			MIDLAND
		STATE:			MI
		ZIP:			48640
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-08-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000019612</issuerCik>
        <issuerName>CHEMICAL FINANCIAL CORP</issuerName>
        <issuerTradingSymbol>(CHFC)</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001213664</rptOwnerCik>
            <rptOwnerName>REISNER JOHN A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>333 E MAIN ST</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MIDLAND</rptOwnerCity>
            <rptOwnerState>MI</rptOwnerState>
            <rptOwnerZipCode>48640</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Officer of Principal Bus. Unit</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-08-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>34.13</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9245</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3074.238</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>401(k) plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3682</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Wife</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Between April 1, 2005 and June 30, 2005 the reporting person acquired 19.074 shares of Chemical Financial Corporation Stock under the Chemical Financial Corporation 401(k) plan.</footnote>
        <footnote id="F2">The reporting person disclaims any beneficial ownership of the shares owned by his wife.  The filing of this statement shall not be construed as an admission that the reporting person is, for purposes of Section 16 of the Securities Exchange Act of 1934 or for any other purpose, the beneficial owner of the securities owned by his wife.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ John A. Reisner</signatureName>
        <signatureDate>2005-08-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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