Abstract: The adsorption behavior of Am(Ⅲ) on Al₂O₃ and quartz were studied in BS03 well groundwater(sampled from drilling well BS03 at Beishan(BS) area—a potential site for China’s high level radioactive waste repository) by a batch technique at （25±1） ℃. The influences of pH， sulphate ion， total carbonate ion， humic acid， and concentration of the Am(Ⅲ) on the adsorption behavior were also studied， and the possible adsorption mechanisms were discussed. After adsorption equilibrium of Am(Ⅲ) on Al₂O₃ and quartz, the desorption behavior of Am(Ⅲ) from Al₂O₃ and quartz were studied with 1.0 mol/L HCl. Experimental results show that the adsorption distribution ratio of Am(Ⅲ) on Al₂O₃ and quartz increases with pH value of the aqueous phase increasing. The chemical composition of the groundwater is the main factor to influence the species of Am(Ⅲ) and adsorption. The adsorption mechanism of Am(Ⅲ) on Al₂O₃ and quartz are surface complexation. The adsorption isotherm of Am(Ⅲ) on Al₂O₃ and quartz can be described by the Freundlich’s equation.