In　this　paper,　an　FEM-BEM　coupling　method　is　presented　to　study　the　steady-state　heat　transfer　problem.　In　the　analysis　of　some　complex　structures,　the　FEM-BEM　coupling　method　has　many　advantages.　These　advantages　are:　(i)　The　degrees　of　freedom　can　be　highly　reduced　using　the　boundary　elements;　(ii)　The　improved　accuracy　of　solution　over　classical　FEM;　(iii)　The　use　of　powerful　pre-/postprocessing　module　of　the　finite　element　software　(ABAQUS);　(iv)　The　improved　efficiency　of　solving　multiscale　structures.　In　this　work,　the　user-defined　element　(UEL)　subroutine　in　ABAQUS　is　used　to　realize　the　coupling　of　ABAQUS　and　BEM.　The　model　is　divided　into　several　parts　and　different　methods　will　be　used　over　different　part.　In　the　implementation　of　the　coupling　scheme,　BEM　part　can　be　assembled　into　the　ABAQUS　as　a　super-element.　And　the　coupling　stiffness　matrix　which　is　consisted　of　the　true　stiffness　matrix　of　BEM　and　the　stiffness　matrix　of　FEM　can　be　obtained.　Then　the　resulted　system　equations　can　be　solved　by　the　solver　of　ABAQUS.　Results　obtained　by　this　coupling　method　have　an　excellent　agreement　compared　with　the　analytical　or　reference　solutions.　　©　2021　WIT　Press.