-----BEGIN PRIVACY-ENHANCED MESSAGE-----
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,
 MMM82OqG200HmSfc0Cu+SjeDpuNWKQ5XiC4isxICYW6/fRxn7GO5JSuqCmDDbMYB
 4IQ45/jAe6bXFdegWBaz5A==

<SEC-DOCUMENT>0000909108-11-000012.txt : 20110211
<SEC-HEADER>0000909108-11-000012.hdr.sgml : 20110211
<ACCEPTANCE-DATETIME>20110211131539
ACCESSION NUMBER:		0000909108-11-000012
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101231
FILED AS OF DATE:		20110211
DATE AS OF CHANGE:		20110211

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DIAMOND HILL INVESTMENT GROUP INC
		CENTRAL INDEX KEY:			0000909108
		STANDARD INDUSTRIAL CLASSIFICATION:	INVESTMENT ADVICE [6282]
		IRS NUMBER:				650190407
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		325 JOHN H MCCONNELL BLVD
		STREET 2:		SUITE 200
		CITY:			COLUMBUS
		STATE:			OH
		ZIP:			43215
		BUSINESS PHONE:		6142553333

	MAIL ADDRESS:	
		STREET 1:		325 JOHN H MCCONNELL BLVD
		STREET 2:		SUITE 200
		CITY:			COLUMBUS
		STATE:			OH
		ZIP:			43215

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BANC STOCK GROUP INC
		DATE OF NAME CHANGE:	19971016

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HEARTLAND GROUP OF COMPANIES INC
		DATE OF NAME CHANGE:	19940301

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HEARTLAND FINANCIAL GROUP INC
		DATE OF NAME CHANGE:	19930714

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LAIRD JAMES F JR
		CENTRAL INDEX KEY:			0001234501

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-24498
		FILM NUMBER:		11596755

	MAIL ADDRESS:	
		STREET 1:		375 N FRONT STREET
		STREET 2:		SUITE 300
		CITY:			COLUMBUS
		STATE:			OH
		ZIP:			43215
</SEC-HEADER>
<DOCUMENT>
<TYPE>5
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>5</documentType>

    <periodOfReport>2010-12-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <form3HoldingsReported>0</form3HoldingsReported>

    <form4TransactionsReported>0</form4TransactionsReported>

    <issuer>
        <issuerCik>0000909108</issuerCik>
        <issuerName>DIAMOND HILL INVESTMENT GROUP INC</issuerName>
        <issuerTradingSymbol>DHIL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001234501</rptOwnerCik>
            <rptOwnerName>LAIRD JAMES F JR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>325 JOHN H MCCONNELL BLVD</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>COLUMBUS</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>43215</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CFO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common</value>
            </securityTitle>
            <transactionCoding>
                <transactionFormType></transactionFormType>
            </transactionCoding>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>65872</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common</value>
            </securityTitle>
            <transactionCoding>
                <transactionFormType></transactionFormType>
            </transactionCoding>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2424</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 401k</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>Gary Young by POA</signatureName>
        <signatureDate>2011-02-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
