-----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,
 DitceQm/R5oPTJJrenkUtFqFv+X9XdNySVLe5d2LEaVGr8Gsy9Jqv7fbuZQ0wGN7
 snEb4a6ueeBugg2BzDGxyA==

<SEC-DOCUMENT>0001140361-08-027003.txt : 20081203
<SEC-HEADER>0001140361-08-027003.hdr.sgml : 20081203
<ACCEPTANCE-DATETIME>20081203164454
ACCESSION NUMBER:		0001140361-08-027003
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080930
FILED AS OF DATE:		20081203
DATE AS OF CHANGE:		20081203

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Motto Todd W
		CENTRAL INDEX KEY:			0001341216

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14902
		FILM NUMBER:		081227871

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		513-271-3700

	MAIL ADDRESS:	
		STREET 1:		C/O MERIDIAN BIOSCIENCE, INC.
		STREET 2:		3471 RIVER HILLS DRIVE
		CITY:			CINCINNATI
		STATE:			OH
		ZIP:			45244

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MERIDIAN BIOSCIENCE INC
		CENTRAL INDEX KEY:			0000794172
		STANDARD INDUSTRIAL CLASSIFICATION:	IN VITRO & IN VIVO DIAGNOSTIC SUBSTANCES [2835]
		IRS NUMBER:				310888197
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		3471 RIVER HILLS DR
		CITY:			CINCINNATI
		STATE:			OH
		ZIP:			45244
		BUSINESS PHONE:		5132713700

	MAIL ADDRESS:	
		STREET 1:		3471 RIVER HILLS DRIVE
		CITY:			CINCINNATI
		STATE:			OH
		ZIP:			45244

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MERIDIAN DIAGNOSTICS INC
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>5
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 5
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>5</documentType>

    <periodOfReport>2008-09-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <form3HoldingsReported>0</form3HoldingsReported>

    <form4TransactionsReported>0</form4TransactionsReported>

    <issuer>
        <issuerCik>0000794172</issuerCik>
        <issuerName>MERIDIAN BIOSCIENCE INC</issuerName>
        <issuerTradingSymbol>VIVO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001341216</rptOwnerCik>
            <rptOwnerName>Motto Todd W</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3471 RIVER HILLS DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CINCINNATI</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>45244</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, Sales and Marketing</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-02-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value>L</value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>363</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>266906</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionCoding>
                <transactionFormType></transactionFormType>
            </transactionCoding>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>126</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Trusts</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">This amount corrects the amount of shares directly held by the reporting person as previously reported.</footnote>
        <footnote id="F2">This amount corrects the amount of shares held by the reporting person in his capacity as the beneficiary of certain irrevocable trusts as previously reported.  The reporting person disclaims beneficial ownership of these shares.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Melissa Lueke as Attorney-in-Fact for Todd W. Motto</signatureName>
        <signatureDate>2008-12-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----