Reduced-graphene-nanoribbon supported nickel doped CoS spheres (Ni-CoS/rGN) have been successfully constructed. The hierarchical structured sphere assembles by spindle-type nanorods features high surface area and good hydrophilicity property. Excellent OER/ORR activities and long-term stabilities are obtained on Ni-CoS/rGN relative to Pt/C and RuO. Density functional theory calculations demonstrate that nickel dopants in CoS structure effectively optimizes the adsorption properties at the rate-determining steps. Therefore, the synergistic regulation between the rGN covered hierarchical structure and nickel dopants by promoting the intrinsic ORR/OER properties, electrical conductivity, and mass transfer is responsible to the superior catalytic performance. Moreover, as a bi-functional catalyst for liquid and flexible Zn–air batteries, Ni-CoS/rGN based battery exhibits excellent battery performance, especially high power density, superior rate performance and long-term cycling stability, providing a new vision for the preparation of high-efficiency catalysts in energy conversion.