Given the increasing attention to the safety issues of lithium-ion batteries (LIBs) and the continuous rise in the price of lithium and its compounds, it is urgent to explore innovative electrochemical energy device alternatives to LIBs. Major efforts have been devoted to developing rechargeable aluminum-ion batteries (AIBs), owing to their low cost and high energy density derived from the 3-electron redox reaction. Moreover, the dendrite-free plating behavior with room-temperature ionic liquid electrolytes endows AIBs with great safety expectations. A marked hurdle persists in the quest for appropriate cathode materials that can effectively accommodate aluminum ion species in AIBs. This review aims to deliver an integrated overview of the state-of-the-art cathode materials for nonaqueous and aqueous AIBs, with a special emphasis on their underlying electrochemical interaction with electrolytes. The strategies adopted to improve the specific capacity and cyclic performances of AIBs are highlighted. Furthermore, future perspectives of AIBs are discussed.