Abstract: The deep purification of heavy metal ions in manganese sulfate solution and the comprehensive utilization of electrolytic manganese anode slag have always been the research focus in the manganese industry. In this paper, electrolytic manganese anode slag was characterized by XRD, SEM, EDS, FT-IR and Zeta spectroscopy. The adsorption behavior of molybdenum in manganese sulfate solution by electrolytic manganese anode slag was studied by orthogonal test analysis and Visual Minteq software adsorption simulation. The results showed that the main components of electrolytic manganese anode slag were α-MnO₂, and the morphology was a rod-like structure with abundant pores. There were many surface hydroxyl groups, and the isoelectric point (IEP) was 3.6. The order of influence of the reaction conditions on the adsorption behavior was as follows: manganese sulfate solution pH > manganese dioxide addition > reaction time. How the ion forms of Mn and Mo in manganese sulfate solution changed with pH was simulated. The surface complexation simulation and experimental data of anode slag at different pH values were compared. It was proven that the adsorption of molybdenum ions resulted from the combination of the surface hydroxyl complexation, surface charge attraction and defect pores of anode slag. This would provide support for solving the problems of difficulty in removing heavy metal ions in manganese sulfate solution and the rational utilization of electrolytic manganese anode slag.