Coastal　wetlands　are　ecosystems　lying　between　land　and　ocean　and　are　subject　to　inputs　of　heavy　metals　(HMs)　from　terrestrial,　oceanic　and　atmospheric　sources.　Although　the　study　on　HM　pollution　in　coastal　wetlands　has　been　rapidly　developing　over　the　past　three　decades,　systematic　reviews　are　still　unavailable.　Here,　by　analyzing　3343　articles　published　between　1990　and　2019,　we　provided　the　first　holistic　systematic　review　of　studies　on　HM　pollution　in　coastal　wetlands　globally.　The　results　showed　a　trend　of　rapid　increases　in　publications　in　this　field　globally,　especially　over　the　past　ten　years.　Trends　varied　greatly　among　coastal　countries,　and　global　trends　were　primarily　driven　by　the　US　before　2000,　and　in　China　after　2010.　We　also　found　that　mercury　(Hg),　cadmium　(Cd),　and　copper　(Cu)　were　the　most　widely　studied　HM　elements　globally,　but　patterns　differed　geographically,　with　Hg　being　most　widely　examined　in　the　Americas,　Cd　in　China　and　India,　and　lead　(Pb)　in　the　western　Europe　and　Australia,　respectively.　Among　different　types　of　coastal　wetlands,　salt　marshes,　mangrove　forests,　and　estuaries　were　the　most　widely　studied,　in　contrast　to　seagrass　beds　and　tidal　flats.　As　for　ecosystem　components,　soils/sediments　and　plants　were　most　extensively　investigated,　while　algae,　microbes,　and　animals　were　much　less　examined.　Our　analysis　further　revealed　rapid　emergence　of　topics　on　anthropogenic　sources,　interactions　with　other　anthropogenic　environmental　changes　(climate　change　in　particular),　and　control　and　remediation　methodology　in　the　literature　in　the　recent　ten　years.　Moving　forward,　we　highlight　that　future　studies　are　needed　to　i)　better　understand　the　impacts　of　HM　pollution　in　less　studied　coastal　wetland　systems　and　species,　ii)　deepen　current　understanding　of　the　biogeochemical　behaviors　of　HMs　under　anthropogenic　activities,　iii)　examine　interactions　with　other　anthropogenic　environmental　changes,　iv)　conceive　ecological　remediation　(i.e.,　＂ecoremediation＂　as　compared　to　traditional　physiochemical　remediation　and　bioremediation)　strategies,　and　v)　develop　advanced　analysis　instruments　and　methods.　The　perspectives　we　brought　forward　can　help　stimulate　many　new　advances　in　this　field.