Abstract: Magnesium anode AP65 with the addition of manganese was prepared by melting and casting. The electrochemical and corrosion behaviour of AP65 anode in 3.5 % sodium chloride solution was investigated by electrochemical measurement, immersion test and corrosion morphology observation. The results show that manganese can promote the grain refinement and reduce the self corrosion rate of AP65 anode. Magnesium anode AP65 added with manganese can provide a more negative discharge potential than that without the addition of manganese. The Al-Mn inclusions distributing homogeneously in AP65 anode can act as active sites and facilitate the peeling off of the corrosion products during the discharge process, indicating that the electrochemical performance of AP65 anode can be improved by adding manganese element.