The intercalation chalcogenide, [CH3NH3]2xMnxSn3−xS6·0.5H2O (x = 0.5-1.1) (CMS), was synthesized by simply hydrothermal method, which exhibited excellent adsorption properties for the removal of Cd2+/Pb2+. CNS analysis, SEM-EDX, ICP-OES, TG-DTG, XPS, N2 physical-adsorption and XRD were used to characterize the crystal structure, chemical composition and micro-morphologies of CMS material. The results indicated that the CH3NH3+ ions intercalated between the layers can exchange with heavy metal ions in the solution. The pH effect on Cd2+/Pb2+ adsorption was slight and the suitable pH value for Cd2+/Pb2+ removal by CMS materials was between 2 to 7. The equilibrium times were 7 h for 200 mg/L Cd2+ and 2 h for 400 mg/L Pb2+, respectively, and the adsorption kinetics was in agreement with pseudo-second-order kinetic model. The adsorption capacities of the CMS for Cd2+ and Pb2+ were 515 mg/g for Cd2+ and 1053 mg/g at 20 °C, respectively. The Freundlich isotherm was applied to describe the adsorption process, which fit the experimental dates well. Competitive adsorption results showed that the presence of 1 M Na+, Ca2+ or Mg2+ exerted slightly inhibiting effect on Cd2+/Pb2+ adsorption. The reaction temperature also affected the adsorption capacity of CMS. The adsorbed CMS can be considered as an excellent permanent waste form without the risk of lease of heavy metals.