In this research, the corrosion behavior and the electrochemical performances of Al–0.5Mg–0.1Sn–0.02In (wt.%) alloy have been investigated in 2 M NaCl, 4 M NaOH ethanol–10% water, 4 M NaOH solutions. The results show that the optimal electrochemical properties are obtained in 4 M NaOH ethanol–water solutions, and the alloy has higher anodic utilization and lower self-corrosion rate in the solutions compared to 2 M NaCl or 4 M aqueous NaOH. SEM and EIS results of the alloy are in good agreement with corrosion characteristics. By comparison with the electrochemical performance of Zn in 4 M NaOH solutions, the feasibility of using Al–0.5Mg–0.1Sn–0.02In alloy as anode material for a high power density Al–air battery in 4 M NaOH ethanol–water solutions is demonstrated.