Abstract: The cobalt-doped manganese oxide for aqueous zinc-ion battery cathode material was prepared by solvothermal, hydrolyzing and annealing with cobalt nitrate and manganese nitrate as raw materials. The microstructure and electrochemical performance of cobalt-doped manganese oxide was investigated. The results show that the prepared cobalt-doped manganese oxide h-CoMn_3.2O_x had a hierarchical yolk-shell structure, and the porous shell surface was decorated with petal-like nanosheets with radial dimension of more than 100 nm. Both of the shell and nanosheets were composed of primary nanoparticles with average size of 5 nm. Cobalt-doping endowed manganese oxides with small size and delicate structure. h-CoMn_3.2O_x had the manganosite MnO crystal structure. Compared with monometallic manganese oxide, h-CoMn_3.2O_x exhibited relatively large specific surface areas and specific capacities, and had good cyclic stability. The energy-storage behavior of h-CoMn_3.2O_x was attributed to sequent co-insertion of H⁺ and Zn²⁺.