-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 EGwxMyuVFvXY9SWBKqzf21sUh19YV4suVlgUo1DNkcBy5PxtVVr37a21XVkedA/i
 9mpw/STyz5l3gGskdNhPMA==

<SEC-DOCUMENT>0000708955-06-000043.txt : 20060421
<SEC-HEADER>0000708955-06-000043.hdr.sgml : 20060421
<ACCEPTANCE-DATETIME>20060421135141
ACCESSION NUMBER:		0000708955-06-000043
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060421
FILED AS OF DATE:		20060421
DATE AS OF CHANGE:		20060421

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FIRST FINANCIAL BANCORP /OH/
		CENTRAL INDEX KEY:			0000708955
		STANDARD INDUSTRIAL CLASSIFICATION:	NATIONAL COMMERCIAL BANKS [6021]
		IRS NUMBER:				311042001
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		300 HIGH ST
		CITY:			HAMILTON
		STATE:			OH
		ZIP:			45011
		BUSINESS PHONE:		5138674700

	MAIL ADDRESS:	
		STREET 1:		300 HIGH ST
		CITY:			HAMILTON
		STATE:			OH
		ZIP:			45011

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			PORTER BARRY S
		CENTRAL INDEX KEY:			0001167411

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-12379
		FILM NUMBER:		06772105

	BUSINESS ADDRESS:	
		STREET 1:		C/O FIRST FINANCIAL BANCORP
		STREET 2:		300 HIGHSTREET PO BOX 476
		CITY:			HAMILTON
		STATE:			OH
		ZIP:			45012
		BUSINESS PHONE:		5138674951

	MAIL ADDRESS:	
		STREET 1:		385 OLIVER ROAD
		CITY:			CINCINNATI
		STATE:			OH
		ZIP:			45215
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-04-21</periodOfReport>

    <issuer>
        <issuerCik>0000708955</issuerCik>
        <issuerName>FIRST FINANCIAL BANCORP /OH/</issuerName>
        <issuerTradingSymbol>FFBC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001167411</rptOwnerCik>
            <rptOwnerName>PORTER BARRY S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>385 OLIVER ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CINCINNATI</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>45215</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>22304</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>FFBC (Directors Fee Stock Plan)</value>
            </securityTitle>
            <transactionDate>
                <value>2006-04-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>196</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>16.18</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4559</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>2000 (NQ) Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>16.9048</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2001-04-25</value>
            </exerciseDate>
            <expirationDate>
                <value>2010-04-25</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>8663</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8663</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>2003 (NQ) Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>15.58</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2004-04-22</value>
            </exerciseDate>
            <expirationDate>
                <value>2013-04-22</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>8663</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8663</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>Terri J. Ziepfel</signatureName>
        <signatureDate>2006-04-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----