A　novel　method　to　prepare　equipment　section　support　for　flight　vehicle　is　proposed　by　using　lightweight　thermoplastic　composites　prepared　by　selective　laser　sintering　(SLS),　in　order　to　meet　the　requirements　of　lightweight,　rapid　development　and　structure　optimization　in　equipment　section　support.　Considering　the　special　service　environment　of　equipment　section　support,　the　process　parameter　optimization　for　preparing　the　short　carbon　fiber　reinforced　PA12　composites　by　SLS　is　carried　out　and　the　mechanical　property,　thermal　behavior　and　dynamic　mechanical　property　of　the　carbon　fiber　reinforced　nylon12　composites　prepared　by　SLS　are　studied,　and　the　test　results　show　that　the　tensile　strength　is　about　63.8　MPa　with　an　elastic　modulus　of　6.5　GPa,　the　flexural　strength　reached　to　118.06　MPa　and　the　damping　factor　is　0.03-0.06,　which　is　much　higher　than　metal　material,　indicating　a　better　damping　performance.　The　fracture　morphology　of　composites　shows　massive　pores　and　its　bulk　density　is　only　about　1.03　g/cm3,　which　is　far　lower　than　metal　material.　Meanwhile,　several　assemble　methods　are　used　for　the　composites　prepared　by　SLS,　and　the　pulling-out　force　and　failure　behavior　are　assessed.　At　last,　an　equipment　section　support　in　rocket　and　the　optimized　structural　support　are　prepared　by　SLS,　and　the　weight　of　the　optimized　structural　support　is　only　60%　of　the　original.　The　results　of　load　experiment　shows　these　two　supports　both　can　withstand　the　load　of　2　000　N　without　destruction　and　clear　deformation,　which　demonstrated　the　feasibility　and　the　potentials　in　the　aerospace　field　of　proposed　method,　as　the　technical　advantage　of　SLS　in　the　lightweight,　rapid　development　and　structure　optimization.　©　2019　Journal　of　Mechanical　Engineering.