Reduced graphene oxide and NiO composite is prepared by homogeneous coprecipitation and subsequent annealing. Characterizations show that NiO particles have a nanosheet-based microsphere structure and anchor uniformly on the surface of reduced graphene oxide platelets. The RG-O/NiO-based supercapacitors exhibit high specific capacitance of 770Fg−1, and enhanced rate capability. It is found that the electrochemical performance can be enhanced by anchoring NiO particles on the surface of RG-O platelets in the RG-O/NiO composite. This method provides a facile and straightforward approach to distribute NiO nanoparticles onto the surface of RG-O sheets and can be extended to the preparation of other RG-O/metal oxides composite for electrochemical energy storage.