Heavy-metal　contamination　is　a　major　concern,　as　excessive　heavy　metals　produce　environmental　pollution,　and　the　cumulative　effects　of　heavy　metals　in　vivo　pose　a　major　threat　to　human　health.　There　is　an　urgent　need　for　a　rapid,　sensitive,　and　efficient　method　for　detecting　heavy　metals.　Quantum　dots　(QDs)　are　in　the　category　of　semiconductor　nanocrystals　whose　radii　are　less　than　or　close　to　the　exciton　Bohr　radius.　QDs　possess　a　potential　in　the　biological　and　medical　fields　to　function　as　a　new　type　of　fluorescent　marker,　because　of　their　unique　and　tunable　photophysical　properties,　which　include　broad　excitation　spectrum,　narrow　emission　spectrum,　tunable　emission　wavelengths,　and　negligible　photobleaching.　In　recent　years,　QDs　made　significant　progress　in　quantitative　analysis　by　providing　a　new　approach　for　determination　of　chemical　content　analysis.　The　aim　of　this　study　was　to　review　the　research　progress　of　QD　detection　of　heavy　metals　in　water　and　consider　the　challenges　and　future　outlook　for　QD-based　sensors　for　heavy-metal　ions.