Ni–Mo/GO coatings in thickness of 1.5–3 μm were electrodeposited from a citrate bath containing nickel sulfate, sodium molybdate, GO and SDS. The impacts of GO nanosheets on the surface morphology, structure, mechanical properties and corrosion resistance of the NiMo matrix were explored. NiMo alloy shows an amorphous phase with a smooth and compact surface. The codeposited graphene oxide can refine NiMo microstructure, but also can lead to rougher surfaces with defects. Coefficient of friction (COF) of NiMo matrix decreased, and wear resistance and hardness increased in the presence of GO. The corrosion resistance of Ni–Mo/GO would be improved only if GO concentration exceeded 0.2 g L−1. The preferred concentration of GO was 0.2–0.3 g L−1, which showed satisfactory anti-corrosion performance. The corrosion resistance depends not only the amount of GO present but also its dispersed arrangement and distribution. A higher content of GO, a dispersion of particles parallel to the substrate and uniform GO distribution in the metallic matrix can hinder the diffusion of corrosive species, leading to an improved corrosion resistance.