A novel magnetic polystyrene (PS) trioctylamine (TOA) microsphere (Fe3O4/PS/TOA) adsorbent was synthesized by permeation and swelling on porous polystyrene microsphere matrix with a crosslinking degree of 0.5% and applied for removal of simulated radioactive element Ce3+. The morphology, composition and magnetic properties were characterized by SEM, FTIR, TG and VSM. The saturation magnetization of the microspheres enhanced significantly with the increase of the times of penetration-deposition, reached to saturation point of 21.72 emu/g. In addition, the adsorption kinetics showed that the adsorption capacity was 39.7 mg/g, isothermal studies indicated that the equilibrium isotherm was more suitable for the Langmuir model.