Climate　change　is　exerting　unprecedented　impacts　on　marine　habitats,　and　many　sessile　invertebrate　species,　such　as　the　endangered　giant　clam　Tridacna　maxima,　are　particularly　sensitive　to　climate　driven　changes　in　their　environment.　Understanding　its　spatial　distribution　and　conservation　requirements　is　of　crucial　significance　in　formulating　effective　protection　strategies.　However,　the　species　has　been　extensively　harvested　and　depleted　in　many　regions,　leading　to　its　listing　as　endangered　species　by　the　International　Union　for　Conservation　of　Nature　(IUCN).　While　marine　protected　areas　(MPAs)　are　considered　effective　conservation　tools,　it　remains　uncertain　whether　existing　MPAs　adequately　protect　these　vulnerable　giant　clams.　To　enhance　the　management　and　conservation　of　this　species,　we　employed　a　Species　Distribution　Models　(SDMs)　approach,　integrating　occurrence　records　of　T.　maxima　with　environmental　variables,　to　predict　its　potential　distribution　based　on　habitat　suitability　and　capture　spatiotemporal　changes.　Based　on　geographical　and　genetic　variations,　the　T.　maxima　in　the　Indo-Pacific　core　region　is　primarily　divided　into　two　populations:　the　East　Indian　Ocean-South　China　Sea　population　(EIOS)　and　the　West　Pacific-Indonesia　population　(WPI).　We　first　quantified　realized　niche　to　reveal　significant　differences　in　ecological　niche　space　among　different　populations.　Subsequently,　SDMs　were　constructed　at　both　species　and　population　levels,　demonstrating　that　population-level　SDMs　provide　more　reliable　predictions　of　population　distributions　due　to　differential　responses　to　climatic　predictor　variables.　Finally,　we　conducted　an　assessment　to　identify　conservation　gaps　for　T.　maxima　beyond　the　existing　MPAs　and　proposed　recommendations　for　future　establishment　of　MPAs　within　the　current　framework.　Based　on　these　findings,　appropriate　conservation　policies　have　been　proposed　to　effectively　protect　the　habitat　of　different　geographical　populations　of　T.　maxima.　Additionally,　spatiotemporal　predictions　of　habitat　suitability　provide　crucial　information　for　developing　adaptive　management　strategies　for　T.　maxima　in　response　to　climate　change,　including　designing　new　protected　areas　and　adjusting　the　location　and　extent　of　existing　protected　areas　based　on　their　geographical　distribution.