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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 QMX4lU/oWxFpmTcB8ckIDw4uzts4TGOevEygQyQDXdar9KfVVnpzFOPACaHH9yut
 ZNe5Id9hZlNKGu/3bRVVSw==

<SEC-DOCUMENT>0001025835-09-000106.txt : 20091119
<SEC-HEADER>0001025835-09-000106.hdr.sgml : 20091119
<ACCEPTANCE-DATETIME>20091119134137
ACCESSION NUMBER:		0001025835-09-000106
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20091118
FILED AS OF DATE:		20091119
DATE AS OF CHANGE:		20091119

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DECOLA MICHAEL A
		CENTRAL INDEX KEY:			0001417285

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15373
		FILM NUMBER:		091195474

	MAIL ADDRESS:	
		STREET 1:		150 N. MERANEC
		CITY:			CLAYTON
		STATE:			MO
		ZIP:			63105

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ENTERPRISE FINANCIAL SERVICES CORP
		CENTRAL INDEX KEY:			0001025835
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				431706259
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		150 NORTH MERAMEC
		STREET 2:		150 NORTH MERAMEC
		CITY:			CLAYTON
		STATE:			MO
		ZIP:			63105
		BUSINESS PHONE:		3147255500

	MAIL ADDRESS:	
		STREET 1:		150 NORTH MERAMEC
		STREET 2:		150 NORTH MERAMEC
		CITY:			CLAYTON
		STATE:			MO
		ZIP:			63105

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ENTERBANK HOLDINGS INC
		DATE OF NAME CHANGE:	19961024
</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>2009-11-18</periodOfReport>

    <issuer>
        <issuerCik>0001025835</issuerCik>
        <issuerName>ENTERPRISE FINANCIAL SERVICES CORP</issuerName>
        <issuerTradingSymbol>EFSC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001417285</rptOwnerCik>
            <rptOwnerName>DECOLA MICHAEL A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>150 N. MERAMEC</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ST. LOUIS</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>63105</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2095</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-11-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>8.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6000</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares are held jointly with spouse.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Michael A. DeCola</signatureName>
        <signatureDate>2009-11-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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