Facile green and scalable synthesis of low-cost nonprecious metal electrocatalysts which favor a four-electron pathway for the oxygen reduction reaction (ORR) are in great need for high-performance metal-air batteries. Herein, an ultrasonication-assisted synthesis method of preparing MnO nanosheets anchored on carbon black (MnO/Super P Li) ORR catalyst is proposed. Three kinds of MnO nanostructures can be controlled and conformably deposited on Super P Li backbone. The MnO/Super P Li composites facilitates a four-electron ORR process and demonstrates superior stability than the benchmark catalyst Pt/C in alkaline solutions. Moreover, the Zn-air battery using one of the MnO/Super P Li catalysts displays a specific capacity of mA h g and the voltage platform is almost unchanged after discharge for 180 h. The high ORR activity of the hybrid catalyst can be attributed to the MnO nanosheets uniformly grown on the Super P Li three dimensional (3D) framework and the appropriate Mn(Ⅲ)/Mn(Ⅳ) of the MnO/Super P Li composite which can magically catalyze the reduction of hydrogen peroxide. Due to the high ORR activity and the superior stability, low cost MnO/Super P Li catalysts lends itself well to potential applications in renewable energy conversion devices.