In　recent　years,　selective　laser　melting　(SLM)　has　gained　an　important　place　in　fabrication　due　to　their　strong　individualization　which　cannot　be　manufactured　using　conventional　processes　such　as　casting　or　forging.　By　proper　control　of　the　SLM　processing　parameters,　characteristics　of　the　alloy　can　be　optimized.　In　the　present　work,　316L　stainless　steel　(SS),　as　a　widely　used　biomedical　material,　is　investigated　in　terms　of　the　effects　of　scanning　speed　on　in　vitro　biocompatibility　during　SLM　process.　Cytotoxicity　assay　is　adopted　to　assess　the　in　vitro　biocompatibility.　The　results　show　the　scanning　speed　strongly　affects　the　in　vitro　biocompatibility　of　316L　SS　parts　and　with　prolongs　of　incubation　time,　the　cytotoxicity　increase　and　the　in　vitro　biocompatibility　gets　worse.　The　optimal　parameters　are　determined　as　follows:　scanning　speed　of　900　mm/s,　laser　power　of　195　W,　hatch　spacing　of　0.09　mm　and　layer　thickness　of　0.02　mm.　The　processing　parameters　lead　to　the　change　of　surface　morphology　and　microstructures　of　samples,　which　can　affect　the　amount　of　toxic　ions　release,　such　as　Cr,　Mo　and　Co,　that　can　increase　risks　to　patient　health　and　reduce　the　biocompatibility.