The　finite　element　analysis　is　applied　by　exerting　displacement　constraints　on　the　representative　volume　element,　in　order　to　simulate　linear　independent　component　of　the　bending　strain　and　to　the　extract　internal　bending　force.　The　stiffness　matrix　is　computed　according　to　the　constitutive　relation　of　the　internal　forces　and　the　strain.　Finally,　considering　the　temperature　effect　on　the　elastic　constants,　the　macroscopic　equivalent　elastic　constants　are　obtained　according　to　the　temperature.　Meanwhile,　the　finite　element　analysis　method　has　been　adopted　for　equivalent　on　the　thermal　expansion　coefficient　of　the　sandwich　plate　at　different　temperatures.　The　bending　responses　of　the　model　with　and　without　equivalent　are　compared　at　different　temperatures;　the　results　show　that　the　error　is　within　4%,　which　demonstrates　the　validity　of　this　method.