The　rapid　growth　of　various　vehicular　apps　such　as　automotive　navigation　and　in-car　entertainment　has　brought　the　explosion　of　vehicular　data.　Such　a　growth　has　given　rise　to　a　huge　challenge　of　maintaining　the　quality　of　cloud　storage　services　for　the　whole　period　of　storage　in　vehicular　networks.　As　a　result,　poor　quality　of　services　easily　causes　data　corruption　problems　and　thereby　threats　vehicular　data　integrity.　Blockchain,　a　tamper-proofing　technique,　is　considered　a　promising　approach　for　mitigating　data　integrity　risks　in　cloud　storage.　However,　existing　blockchain-based　schemes　for　auditing　long-term　cloud　data　integrity　suffer　from　poor　communication　performance　in　a　vehicular　network.　In　this　study,　a　blockchain-based　offline　auditing　scheme　for　cloud　storage　in　the　vehicular　network　is　proposed　to　improve　auditing　performance.　Inspired　by　the　data　structure　of　blockchain,　we　design　an　evidence　chain　to　achieve　offline　auditing,　which　allows　the　cloud　to　spontaneously　generate　data　integrity　evidence　without　communicating　with　auditors　during　the　evidence　generation　phase.　Furthermore,　we　extend　our　scheme　to　support　public　and　automatic　validation　based　on　the　smart　contract.　We　prove　the　security　of　the　proposed　scheme　under　the　random　oracle　model　and　further　provide　the　performance　evaluation　by　comparing　with　the　state-of-the-art　approaches.