In　response　to　the　problem　of　inconsistent　control　caused　by　the　inevitable　delays　between　the　controller　and　switches　in　the　software　defined　networking　(SDN),　the　average　delay　between　controller　and　switches　in　SDN　are　obtained　through　controller-to-switch　message　through　Openflow　protocol,　and　a　consistent　update　scheme　based　on　shortest　average　delay　(namely　CUSBSAD)　for　control　logic　in　SDN　is　designed.　In　addition,　an　objective　optimization　model　based　on　the　shortest　average　delay　of　nodes　is　constructed.　This　model　is　then　used　to　find　the　minimum-delay　route　while　retaining　the　logical　consistency　in　the　SDN　network.　The　simulation　results　demonstrate　that　the　proposed　scheme　is　feasible　and　effective.