Abstract: A Ni-SiO₂ composite coating was prepared on the surface of a Zr-4 alloy by a direct current electrodeposition method. The surface morphology, microhardness, corrosion behavior and wear resistance of the Ni-SiO₂ composite coating were studied by field emission scanning electron microscopy, microhardness testing, electrochemical testing and friction wear testing. The results showed that the microhardness of the Ni-SiO₂ composite coating was improved compared with that of the Ni coating, and its surface was more uniform and compact. The corrosion and wear resistance of the Ni-SiO₂ composite coating were also significantly improved. In addition, when the additional amount of SiO₂ powder was 10 g/L, the comprehensive performance of the composite coating was best.