Abstract: The imprinting modified magnetic crosslinking chitosan(Pb-TMCS)was prepared to improve the removal ability of chitosan (CS) to Pb²⁺, whose structure and morphology were characterized by FTIR, SEM and XRD, and the adsorption, desorption performance and selectivity of Pb²⁺ on Pb-TMCS were studied. Results show that compared with CS, Pb-TMCS has more pore and fold, and more -OH and-NH₂ are introduced. The magnetic material Fe₃O₄ is embed in Pb-TMCS. The relative selectivity coefficient of Pb-TMCS to CS is more than 2. Pb-TMCS shows higher adsorption capacity (45.26 mg/g) than CS (25.57 mg/g) for Pb²⁺. Pb-TMCS could be used repeatedly after being desorpted 3 times. Recycling of Pb-TMCS is convenient, and it has high selective adsorption for Pb²⁺, and it is non-polluting, so it has good application prospect in treatment of heavy metal waste water.