The　triply　periodic　minimal　surfaces　(TPMS)　can　be　employed　to　realize　the　variable　porosity　gradient　in　different　directions　and　has　a　great　application　prospect　in　the　orthopedic　implant　field.　In　the　present　scrutiny,　two　kinds　of　gyroid-based　TPMS　gradient　scaffolds　(skeletal-gyroid　and　sheet-gyroid)　in　different　orientations　are　established　and　manufactured　by　utilizing　selective　laser　melting　(SLM)　technology　with　Ti-6Al-4V　powders.　The　meshing　of　the　TPMS　based　on　the　voxelization　loses　its　surface　smoothness　and　brings　the　geometric　defects　of　steps.　Therefore,　an　optimized　smoothing-tetrahedral　mesh　strategy　(STMS)　to　finite　element　analysis　(FEA)　is　proposed　to　explore　the　graded　scaffolds＇　overall　deformation　response　and　energy　absorption　efficiency.　The　obtained　results　reveal　that　the　mechanical　properties　of　the　samples　are　slightly　altered　after　heat　treatment.　The　sheet-gyroid　(Sh-G)　structure　has　a　higher　elastic　modulus　and　compressive　strength,　more　stable　energy　absorption　efficiency,　and　higher　total　energy　absorption　compared　with　the　skeletal-gyroid　(Sk-G).　The　fracture　morphology　of　the　Sk-G　exhibits　two　distinct　regions:　a　typical　dimple　of　ductile　fracture　and　a　brittle　fracture　characterized　by　the　flow　pattern,　while　the　Sh-G　samples　only　demonstrate　brittle　fractures.　The　STMS　and　Johnson-Cook　plastic　damage　model　correctly　simulated　the　gradient　porous　scaffolds＇　plastic　deformation　and　failure　behavior　after　yielding.　Furthermore,　the　stress-strain　curves　of　the　simulation　agree　well　with　the　experimental　results　such　that　the　minimum　elastic　modulus　and　yield　strength　discrepancies　in　order　are　0.5　and　2.8%.　The　STMS　improves　the　simulation　accuracy　of　the　TPMS　structure　and　provides　a　solid　foundation　for　designing　and　applying　artificial　bone　scaffolders　in　the　near　future.