A considerable number of achievements based on cathode materials have been demonstrated for AZIB. Nevertheless, commonly cathode materials are challenged with persistent issues that remain to be further studied and support from key technologies, including weak structural stability, cathode dissolution, severe electrostatic interaction and poor electric conductibility. The energy storage mechanism of manganese dioxide (MnO₂) as the cathode material of AZiBs is more complex than other materials and has been controversial, which is the main factor limiting the application prospect of Zn//MnO₂ batteries. Therefore, this paper provides a comprehensive summary of the characteristics and energy storage mechanisms of the latest MnO2-based cathode materials, critically reviews the basic problems and corresponding deep-seated reasons of MnO₂-based cathode materials, and systematically summarizes and discusses the optimization strategies in recent work reports. Finally, based on the problems existing in different energy storage mechanisms of MnO₂, combined with the latest research progress, a series of key challenges to promote the commercialization of Zn//MnO₂ batteries are summarized, providing relevant ideas and prospects for the future research trend of AZBs.