Additive　manufacturing　plays　an　indispensable　role　in　the　field　of　complex　structure　forming,　which　enables　the　precise　manufacturing　of　complex　products　directly　through　digital　models.　Among　them,　Selective　Laser　Sintering　(SLS)　technology,　as　an　advanced　technology　for　powder-based　additive　manufacturing,　PA12　is　an　ideal　material　that　can　be　used　in　SLS　technology.　However,　during　the　forming　process,　the　particles　are　connected　by　sinter　necks,　which　often　results　in　microporous　parts　and　high　surface　roughness,　which　prevents　the　intrinsic　properties　of　the　material　from　being　achieved.　In　order　to　improve　the　mechanical　properties　of　SLS　molded　parts,　three　methods　are　usually　applied:　first,　the　process　parameters　are　optimized,　which　is　a　relatively　simple　method,　but　usually　the　material　properties　are　not　greatly　improved;　the　second　is　to　enhance　the　performance　of　the　part　by　introducing　reinforcement,　which　can　indeed　bring　about　the　improvement　of　the　performance　of　the　molded　parts,　but　it　is　usually　difficult　to　form,　and　at　the　same　time　will　cause　many　problems　such　as　the　surface　quality　of　the　molded　parts;　finally,　this　situation　is　improved　by　post-treatment　of　the　formed　parts,　which　is　also　a　good　way　to　improve　the　mechanical　properties　of　the　molded　parts,　which　are　commonly　improved　by　heat　treatment,　but　this　method　often　leads　to　the　deformation　of　the　parts　after　heat　treatment,　which　is　usually　caused　by　overheating　and　slow　cooling.　In　order　to　solve　this　problem,　this　paper　independently　developed　a　uniform　heating　and　rapid　cooling　device　for　heat　treatment　of　SLS-printed　PA12　materials　and　complex　structural　parts.　It　aims　to　achieve　the　intrinsic　mechanical　properties　of　the　material　by　improving　the　internal　structural　defects　of　the　material.　The　properties　of　the　heat-treated　sample　were　greatly　improved　at　room　temperature,　with　a　maximum　tensile　strength　of　(57.6　+/-　1.9)　MPa　and　an　elongation　at　break　between　293　degrees　o　and　297　degrees　o.　In　addition,　the　material　still　maintains　good　tensile　properties　in　high　and　low　temperature　environments,　with　a　tensile　strength　of　up　to　110.5　MPa　and　an　elongation　at　break　of　22　degrees　o　to　25　degrees　o　at　-80　degrees　C　.　The　tensile　strength　at　+80　degrees　C　is　(53.1　+/-　3.3)　MPa,　and　the　elongation　at　break　is　up　to　578.6　degrees　o.　The　load-bearing　capacity　of　the　heat-treated　samples　with　Triply　Periodic　Minimal　Surfaces　(TPMS)　structures　increased　by　up　to　19　degrees　o　in　the　elastic　stage.　Among　them,　the　heat-treated　D-type　TPMS　performed　excellently,　with　a　maximum　load-bearing　capacity　of　7.3　kN　in　the　elastic　stage　and　excellent　energy　absorption　performance.　At　the　same　time,　this　study　found　that　with　the　gradual　increase　of　temperature,　the　tensile　properties　basically　increased　first　and　then　decreased.　There　is　little　difference　between　the　crystallinity　and　the　peak　melting　temperature　of　the　unheat-treated　specimen　and　the　specimen　under　different　heat-treated　temperatures,　and　the　crystal　form　does　not　change.　With　the　gradual　increase　of　heat　treatment　temperature,　the　surface　roughness　value　of　the　sample　showed　a　gradual　downward　trend,　and　the　roughness　was　the　lowest　at　230　degrees　C　.　After　heat　treatment,　the　porosity　and　defects　in　the　cross-section　of　the　sample　basically　disappeared,　and　the　plastic　deformation　occurred　during　the　tensile　process.　At　the　same　time,　it　can　promote　the　molten　growth　and　microstructure　densification　of　SLS-formed　PA12　specimen　particles,　eliminate　internal　pore　defects,　and　improve　the　mechanical　properties　of　the　material.