Abstract: The extraction resin B4DC6/P120 was synthesized by vacuum perfusion technology. Characterization of B4DC6/P120 were investigated by SEM and FTIR. The effects of contact time, nitric acid concentration, temperature and coexisting ions on the adsorption of Cs⁺ on B4DC6/P120 were investigated by static adsorption experiments. The breakthrough curve was also studied by dynamic adsorption experiment. The results show that the adsorption equilibrium time of B4DC6/P120 for Cs⁺ is about 24 h, and the adsorption kinetic conforms to the pseudo first-order kinetic equation. As the acidity increases, the adsorption performance increases first and then decreases. Increasing the temperature is conducive to the adsorption. High adsorption performance and selectivity for Cs⁺ is observed, and the separation factor of Cs⁺ towards most cations is more than 10. The results of dynamic removal of Cs⁺ by B4DC6/P120 show good adsorption performance for Cs⁺ and the resin can be used to remove Cs⁺ from radioactive waste liquid.