With　the　developments　of　the　Internet　of　Things,　the　demands　of　low　latency,　high　bandwidth　and　high-performance　computing　has　increased　higher.　Therefore,　the　distributed　computing　named　Fog　Computing　has　proposed　to　solve　the　problem　above.　Fog　computing　can　provide　lower　transmission　latency,　faster　response　time　and　less　network　congestion.　However,　the　fog　devices　are　unable　to　guarantee　the　security　and　privacy　of　data　transmission,　due　to　they　are　vulnerable　to　attack.　Blockchain　technology　works　as　a　decentralized　public　ledger　to　store　and　share　transactions.　Blockchain　can　improve　security　and　protect　data　privacy　of　Fog　Computing.　Moreover,　there　are　still　issues　in　the　blockchain-enabled　Fog　Computing,　the　two　main　issues　are　the　energy　consumption　and　computing　efficiency.　Thus,　in　this　paper,　we　propose　an　optimization　framework　for　blockchain-enabled　Fog　Computing　systems　to　optimize　resource　allocation.　Besides,　we　adopt　the　dueling　deep　reinforcement　learning　to　obtain　the　optimal　resource　allocation　strategy,　with　dynamically　selecting　the　fog　server,　offloading　decision,　block　size.　Simulation　results　show　that　the　proposed　framework　can　reduce　the　energy　consumption　and　computation　overhead　of　the　system,　as　well　as　can　improve　the　computing　efficiency.　©　2022　ACM.