Porous flowerlike Co3O4 microspheres/Cu nanoparticles composite has been synthesized via a combined solvothermal method, subsequent thermal treatment and polyol process. Due to the 3D mesoporous structure, the resulting Co3O4 microspheres/Cu catalyst shows an efficient and stable bifunctional catalytic activity. The cobalt oxide-based catalysts show better performance during the discharging and charging processes at a current density of 0.05 mA cm− 2 compared with that of the Vulcan XC-72. The cell with this novel catalyst can be reversibly charged/discharged and has a good cycle performance. The preliminary results indicate that the Porous flowerlike Co3O4 microspheres/Cu nanoparticles composite is a promising material for a metal/air battery or a PEM fuel cell as an efficient and stable bifunctional catalyst.