<SEC-DOCUMENT>0001415889-17-001044.txt : 20170626
<SEC-HEADER>0001415889-17-001044.hdr.sgml : 20170626
<ACCEPTANCE-DATETIME>20170626170756
ACCESSION NUMBER:		0001415889-17-001044
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170525
FILED AS OF DATE:		20170626
DATE AS OF CHANGE:		20170626

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MERCANTILE BANK CORP
		CENTRAL INDEX KEY:			0001042729
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				383360865
		STATE OF INCORPORATION:			MI
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		310 LEONARD STREET NW
		CITY:			GRAND RAPIDS
		STATE:			MI
		ZIP:			49504
		BUSINESS PHONE:		616 406-3000

	MAIL ADDRESS:	
		STREET 1:		310 LEONARD STREET NW
		CITY:			GRAND RAPIDS
		STATE:			MI
		ZIP:			49504

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GARDNER JEFF A
		CENTRAL INDEX KEY:			0001337974

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-26719
		FILM NUMBER:		17930507

	MAIL ADDRESS:	
		STREET 1:		C/O FIRSTBANK CORPORATION
		STREET 2:		311 WOODWORTH AVENUE
		CITY:			ALMA
		STATE:			MI
		ZIP:			48801
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4-06262017_020645.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-05-25</periodOfReport>

    <issuer>
        <issuerCik>0001042729</issuerCik>
        <issuerName>MERCANTILE BANK CORP</issuerName>
        <issuerTradingSymbol>MBWM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001337974</rptOwnerCik>
            <rptOwnerName>GARDNER JEFF A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MERCANTILE BANK CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>310 LEONARD STREET</rptOwnerStreet2>
            <rptOwnerCity>GRAND RAPIDS</rptOwnerCity>
            <rptOwnerState>MI</rptOwnerState>
            <rptOwnerZipCode>49504</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>true</isDirector>
            <isOfficer>false</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-05-25</value>
                <footnoteId id="F1"/>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>750</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15131</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by Jeff Gardner &amp; Susan Gardner Weinberg as joint tenants</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>52864</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by Trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by Norma Gardner Trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by IRA</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">This Form 4 is being filed late due to an administrative oversight.</footnote>
        <footnote id="F2">Includes shares acquired since his last report of common stock ownership by reinvesting cash dividends under the issuer's dividend reinvestment plan, as well as an adjustment reflecting the allocation of 2,612 shares from direct holdings to trust holdings.</footnote>
        <footnote id="F3">Reflects an additional 2,612 shares since the reporting person's last report on Form 4, which were previously reported in his direct holdings.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Bradley J. Wyatt, Attorney-in-Fact</signatureName>
        <signatureDate>2017-06-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
