The electrochemical behavior and purification method and principle of typical Cu2+ impurity in the recovery process of waste lead paste based on Methanesulfonic acid (MSA) were studied. The research results show that Cu2+ is preferentially precipitated over Pb2+ in the electrolysis process, resulting in a decrease in the purity of electrolytic lead, a decrease in the current efficiency of lead reduction and an increase in energy consumption. The existence of Cu2+ changes the nucleation mechanism of Pb2+, thus making the reduction potential of Pb2+ shift positively. Based on the principle of removing copper with lead powder, the fluidized purification process is proposed to replace the traditional stirring replacement method according to the characteristics of lead methanesulfonate system, which solves the problems of the large consumption of lead powder, high purification cost, and low efficiency. When the particle size of lead powder is 100 ~ 150 mesh, the temperature is 20 ℃, the flow rate is 8 ~ 10 m/h, and the height of the filled lead powder column is 0.6 ~ 0.7 cm. The removal rate of Cu2+ can reach more than 90% in the purification process of actual leaching solution from waste lead paste.