Wireless　sensor　networks　(WSNs)　play　a　very　important　role　in　the　Internet　of　Things.　But,　how　to　save　the　energy　of　the　wireless　sensor　nodes　and　prolong　the　lifetime　of　such　networks　is　an　emergent　task　for　the　wide　adoption　of　the　networks.　Considering　the　characteristics　of　wireless　sensor　nodes　where　energy　consumption　for　transmitting　data　is　much　more　than　that　for　computation,　this　paper　presents　method　for　precalculating　a　secure　and　efficient　path　before　data　transmission　begins.　The　basic　idea　of　the　proposed　method　is　that　the　path　length　based　Floyd　algorithm　and　trust　degree　between　neighboring　nodes　are　used　as　the　reference　for　the　selection　of　the　routes.　Data　is　then　transmitted　along　the　secure　and　efficient　path　in　the　WSNs.　©　2013　by　IFSA.