Abstract: A method for determination of Pd²⁺ in simulated high-level liquid waste was studied by using CdSe/ZnS quantum dots capped with carboxyl as fluorescence probe. Under optimum conditions, the presence of Pd²⁺ results in fluorescent quench of CdSe/ZnS quantum dots. So the quantitative relation between fluorescence of quantum dots and concentration of Pd²⁺ can be built. The results show that a good linear relationship exists in the concentration range from 0.04-0.96 mg/L. The proposed method is used to determine the concentration of Pd²⁺ in simulated high-level liquid waste, with the relative bias of better than 8%, and the relative standard deviation（s_r） better than 4%(n=6). The recovery ranges from 97.8%-109.1%. The developed method is highly sensitive, well selective, rapid and economical.