For　group　signature(GS)supporting　membership　revocation,verifier-local　revocation(VLR)mechanism　seems　to　be　a　more　flexible　choice,because　it　requires　only　that　verifiers　download　up-to-date　revocation　information　for　signature　verification,and　the　signers　are　not　involved.As　a　post-quantum　secure　cryptographic　counterpart　of　classical　number-theoretic　cryptographic　constructions,the　first　lattice-based　VLR　group　signature(VLR-GS)was　introduced　by　Langlois　et　al.(2014).However,none　of　the　contemporary　lattice-based　VLR-GS　schemes　provide　backward　unlinkability(BU),which　is　an　important　property　to　ensure　that　previously　issued　signatures　remain　anonymous　and　unlinkable　even　after　the　corresponding　signer(i.e.,member)is　revoked.In　this　study,we　introduce　the　first　lattice-based　VLR-GS　scheme　with　BU　security(VLR-GS-BU),and　thus　resolve　a　prominent　open　problem　posed　by　previous　works.Our　new　scheme　enjoys　an(O)(log　N)factor　saving　for　bit-sizes　of　the　group　public-key(GPK)and　the　member＇s　signing　secret-key,and　it　is　free　of　any　public-key　encryption.In　the　random　oracle　model,our　scheme　is　proven　secure　under　two　well-known　hardness　assumptions　of　the　short　integer　solution(SIS)problem　and　learning　with　errors(LWE)problem.