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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2010-03-05</periodOfReport>

    <dateOfOriginalSubmission>2010-03-09</dateOfOriginalSubmission>

    <issuer>
        <issuerCik>0001473061</issuerCik>
        <issuerName>PostRock Energy Corp</issuerName>
        <issuerTradingSymbol>PSTR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001440974</rptOwnerCik>
            <rptOwnerName>Hammond Gabriel Arce</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2100 MCKINNEY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>14TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001427131</rptOwnerCik>
            <rptOwnerName>SteelPath Capital Management LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2100 MCKINNEY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>14TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001492041</rptOwnerCik>
            <rptOwnerName>SP Opportunity Advisors IV LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2100 MCKINNEY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>14TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001490671</rptOwnerCik>
            <rptOwnerName>SP Opportunity Partners IV LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2100 MCKINNEY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>14TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001492350</rptOwnerCik>
            <rptOwnerName>SP Opportunity Advisors IX LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2100 MCKINNEY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>14TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001490659</rptOwnerCik>
            <rptOwnerName>SP Opportunity Partners IX LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2100 MCKINNEY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>14TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001492340</rptOwnerCik>
            <rptOwnerName>SP Capital Advisors LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2100 MCKINNEY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>14TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001298280</rptOwnerCik>
            <rptOwnerName>SCM Capital Partners LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2100 MCKINNEY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>14TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001492349</rptOwnerCik>
            <rptOwnerName>SP Focus Advisors LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2100 MCKINNEY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>14TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001370844</rptOwnerCik>
            <rptOwnerName>SP Focus Partners LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2100 MCKINNEY AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>14TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>999420</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>999420</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Through funds</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>791633</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>791633</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>142334</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>142334</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F5"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>49869</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>48869</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F6"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>15584</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15584</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F7"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares may be deemed to be beneficially and indirectly owned by SteelPath Capital Management LLC (&quot;Management&quot;) and Gabriel A. Hammond, a director of the issuer. Management serves as investment advisor to the funds listed in footnote 2.  Mr. Hammond is the manager and a member of Management and of each of the general partners.  Each of Mr. Hammond and Management disclaims beneficial ownership of such shares except to the extent of their respective pecuniary interest therein and this report shall not be deemed an admission of beneficial ownership of such shares for purposes of Section 16 or for any other purpose.</footnote>
        <footnote id="F2">Pursuant to the Merger Agreement dated July 2, 2009, as amended, between Quest Resource Corporation, Quest Midstream Partners, L.P. (&quot;QMLP&quot;) and Quest Energy Partners, L.P. and the other parties thereto, all of the common units in QMLP and membership interests in Quest Midstream GP, LLC (&quot;QMGP&quot;) were converted into shares of common stock of the issuer at the effective time of the merger.  SP Opportunity Partners IV LP directly owned 1,949,461 QMLP common units and 75 membership interests in QMGP, which converted into 791,633 shares of the issuer at the effective time. SP Opportunity Partners IX LP directly owned 352,922 QMLP common units, which converted into 142,334 shares of the issuer at the effective time. SCM Capital Partners LP directly owned 123,652 QMLP common units, which converted into 49,869 shares of the issuer at the effective time. SP Focus Partners LP directly owned 38,641 QMLP common units, which converted into 15,584 shares of the issuer at the effective time.</footnote>
        <footnote id="F3">The acquisition of the shares was an exempt transaction approved by the board of directors of the issuer pursuant to Rule 16b-3 of the Securities Exchange Act of 1934 (the &quot;Exchange Act&quot;).</footnote>
        <footnote id="F4">These shares are owned directly by SP Opportunity Partners IV LP.  SP Opportunity Advisors IV LLC is the general partner of SP Opportunity Partners IV LP and may be deemed to be the indirect beneficial owner of these shares.</footnote>
        <footnote id="F5">These shares are owned directly by SP Opportunity Partners IX LP.  SP Opportunity Advisors IX LLC is the general partner of SP Opportunity Partners IX LP and may be deemed to be the indirect beneficial owner of these shares.</footnote>
        <footnote id="F6">These shares are owned directly by SCM Capital Partners LP.  SP Capital Advisors LLC is the general partner of SCM Capital Partners LP and may be deemed to be the indirect beneficial owner of these shares.</footnote>
        <footnote id="F7">These shares are owned directly by SP Focus Partners LP.  SP Focus Advisors LLC is the general partner of SP Focus Partners LP and may be deemed to be the indirect beneficial owner of these shares.</footnote>
    </footnotes>

    <remarks>Gabriel Hammond, Management, SP Opportunity Partners IV LP, SP Opportunity Advisors IV LLC, SP Opportunity Partners IX LP, SP Opportunity Advisors IX LLC, SCM Capital Partners LP, SP Capital Advisors LLC, SP Focus Partners LP and SP Focus Advisors LLC (collectively, the &quot;Reporting Persons&quot;) may be deemed members of a &quot;group&quot; for purposes of Section 13(d) of the Exchange Act.  Mr. Hammond may be deemed to serve on the board of directors of the issuer as a representative of each of the aforementioned entities and such entities may be deemed to be directors by deputization.  The filing of this report and the inclusion of information herein shall not be considered an admission that any Reporting Person is in fact a member of such a &quot;group&quot; or that such Reporting Person has any liability or obligation under Section 16(b) of the Exchange Act in connection with any such &quot;group&quot; or that for purposes of Section 16 or any other purpose, such Reporting Person is the beneficial owner of any securities in which such Reporting Person does not have a pecuniary interest.  Each Reporting Person expressly disclaims beneficial ownership of the shares reported herein to the fullest extent permitted by applicable law.</remarks>

    <ownerSignature>
        <signatureName>/s/ Gabriel A. Hammond</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Gabriel A. Hammond, manager of SteelPath Capital Management LLC</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Gabriel A. Hammond, manager of SP Opportunity Advisors IV LLC</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Gabriel A. Hammond, manager of SP Opportunity Advisors IX LLC</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Gabriel A. Hammond, manager of SP Capital Advisors LLC</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Gabriel A. Hammond, manager of SP Focus Advisors LLC</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Gabriel A. Hammond, manager of SP Opportunity Advisors IV LLC, general partner of SP Opportunity Partners IV LP</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Gabriel A. Hammond, manager of SP Opportunity Advisors IX LLC, general partner of SP Opportunity Partners IX LP</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Gabriel A. Hammond, manager of SP Capital Advisors LLC, general partner of SCM Capital Partners LP</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Gabriel A. Hammond, manager of SP Focus Advisors LLC, general partner of SP Focus Partners LP</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
