A　nanosheet-like　K/Zn/Sn/S　metal　sulfide　(KZTS-NS)　was　synthesized　by　a　hydrothermal　method.　The　adsorption　properties　and　mechanism　of　KZTS-NS　towards　Cs+　was　investigated.　The　results　showed　that　fast　adsorption　of　Cs+　occurred　by　KZTS-NS　with　an　equilibrium　time　of　only　10　minutes　and　Cs+　removal　rate　of　96.50%.　The　adsorption　isotherms　were　well　fitted　with　the　Langmuir　model,　and　the　calculated　maximum　adsorption　capacity　reached　133.96　mg·g−1,　which　was　higher　than　other　reported　adsorbents.　The　adsorption　of　Cs+　by　KZTS-NS　was　a　spontaneous,　endothermic,　and　entropy-increasing　process.　KZTS-NS　had　a　good　performance　on　Cs+　adsorption　in　the　pH　range　of　3-10.　The　inhibitory　effect　of　coexisting　ions　on　Cs+　adsorption　by　KZTS-NS　followed　the　sequence　of　Mg2+＞Ca2+＞Na+＞K+.　The　removal　rates　of　Cs+　by　KZTS-NS　in　tap　water,　mineral　water,　lake　water,　and　seawater　were　42.14%,　25.15%,　14.14%,　and　4.44%,　respectively.　The　KZTS-NS　before　and　after　cesium　ion　(Cs+)　adsorption　was　characterized　using　scanning　electron　microscopy　(SEM),　X-ray　diffraction　(XRD),　and　X-ray　photoelectron　spectroscopy　(XPS),　etc.　to　reveal　the　Cs+　adsorption　mechanism.　Results　showed　that　the　nanosheet-like　morphology　of　KZTS-NS　remained　unchanged　before　and　after　adsorption　of　Cs+.　K,　Zn,　Sn,　and　S　elements　were　evenly　distributed　on　the　surface　of　KZTS-NS.　The　XRD　characteristic　peaks　after　Cs+　adsorption　shifted　towards　a　lower　2θ　value,　corresponding　to　an　increase　in　crystal　plane　spacing.　The　XPS　spectra　and　quantitative　analysis　indicated　that　the　adsorption　mechanism　of　KZTS-NS　for　Cs+　was　ion　exchange.　In　summary,　KZTS-NS　could　rapidly　and　efficiently　remove　Cs+　from　wastewater　and　showed　a　great　potential　for　further　application.　This　study　provides　a　technical　reference　and　the　basic　data　supports　for　the　treatment　of　wastewater　containing　radioactive　Cs+　ions.　©　2024　Science　Press.　All　rights　reserved.