-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 PI4Yq+S3xbka79x7rt4jkVZTtAyeelu5WcAwDZxR0mKvaQRcmrRQbjDHOB+XktyN
 4INAXNdmy1MpU4e0euYIoA==

<SEC-DOCUMENT>0001127602-10-006839.txt : 20100302
<SEC-HEADER>0001127602-10-006839.hdr.sgml : 20100302
<ACCEPTANCE-DATETIME>20100302152410
ACCESSION NUMBER:		0001127602-10-006839
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100301
FILED AS OF DATE:		20100302
DATE AS OF CHANGE:		20100302

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Stafford Richard William
		CENTRAL INDEX KEY:			0001365454

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-16772
		FILM NUMBER:		10648972

	MAIL ADDRESS:	
		STREET 1:		138 PUTNAM STREET
		STREET 2:		P.O. BOX 738
		CITY:			MARIETTA
		STATE:			OH
		ZIP:			45750

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PEOPLES BANCORP INC
		CENTRAL INDEX KEY:			0000318300
		STANDARD INDUSTRIAL CLASSIFICATION:	NATIONAL COMMERCIAL BANKS [6021]
		IRS NUMBER:				310987416
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			0202

	BUSINESS ADDRESS:	
		STREET 1:		138 PUTNAM ST
		STREET 2:		P O BOX 738
		CITY:			MARIETTA
		STATE:			OH
		ZIP:			45750-0738
		BUSINESS PHONE:		7403733155

	MAIL ADDRESS:	
		STREET 1:		138 PUTNAM ST
		STREET 2:		P O BOX 738
		CITY:			MARIETTA
		STATE:			OH
		ZIP:			45750-0738
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-03-01</periodOfReport>

    <issuer>
        <issuerCik>0000318300</issuerCik>
        <issuerName>PEOPLES BANCORP INC</issuerName>
        <issuerTradingSymbol>PEBO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001365454</rptOwnerCik>
            <rptOwnerName>Stafford Richard William</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>138 PUTNAM STREET</rptOwnerStreet1>
            <rptOwnerStreet2>P.O. BOX 738</rptOwnerStreet2>
            <rptOwnerCity>MARIETTA</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>45750</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>Executive Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted shares granted from the 2006 Equity Plan, subject to terms of agreement and vesting schedules.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Edward G. Sloane, attorney-in-fact for Mr. Stafford</signatureName>
        <signatureDate>2010-03-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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