Two　analytic　expressions　have　been　proposed　to　solve　the　key　difficulty　of　coupling　LBM　with　other　methods.　These　are　called　density　distribution　reconstruction　operator　and　temperature　distribution　reconstruction　operator.　The　mesoscopic　LBM　is　coupled　upward　with　macroscopic　FVM　and　downward　with　microscopic　MD.　FVM-LBM　coupled　model　is　validated　by　2D　natural　convection　in　a　square　cavity.　LBM-MD　coupled　model　is　applied　to　simulate　Poiseuille　flows.　The　results　are　in　good　agreement　with　benchmark　results,　which　verifies　the　validation　of　the　coupled　models　based　on　the　reconstruction　operators.