<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2021-05-06</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001046102</issuerCik>
        <issuerName>RITCHIE BROS AUCTIONEERS INC</issuerName>
        <issuerTradingSymbol>RBA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001861925</rptOwnerCik>
            <rptOwnerName>Geisner Kevin Alan</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O RITCHIE BROS. AUCTIONEERS INCORPORAT</rptOwnerStreet1>
            <rptOwnerStreet2>9500 GLENLYON PARKWAY</rptOwnerStreet2>
            <rptOwnerCity>BURNABY</rptOwnerCity>
            <rptOwnerState>A1</rptOwnerState>
            <rptOwnerZipCode>V5J0C6</rptOwnerZipCode>
            <rptOwnerStateDescription>BRITISH COLUMBIA, CANADA</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Strategy Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>142</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Employee Stock Purchase Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>57.47</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2021-03-04</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2030-08-11</value>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>20604</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>54.83</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2022-02-24</value>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2031-02-25</value>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>21307</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Includes all Employee Stock Purchase Plan purchases through May 13, 2021.</footnote>
        <footnote id="F2">The option was granted on August 11, 2020 and vests equally in three equal annual installments beginning March 4, 2021.</footnote>
        <footnote id="F3">Date of expiration is reflected above; provided, however, that if such date occurs during a black out period (as defined in the RBA Amended and Restated Stock Option Plan) applicable to the reporting person or within five business days (as defined in such Plan) after the last day of a black out period applicable to the person, the expiry date for the option will be the last day of such five business day period.</footnote>
        <footnote id="F4">The option was granted on February 25, 2021 and vests equally in three equal annual installments beginning February 24, 2022.</footnote>
    </footnotes>

    <remarks>Exhibit 24.1 POWER OF ATTORNEY</remarks>

    <ownerSignature>
        <signatureName>/s/ Maria Teresa Punsalan as attorney-in-fact for Kevin Alan Geisner.</signatureName>
        <signatureDate>2021-05-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
