Abstract: By combining ultrasonic vibration thermal effects conversion with dynamic boundary conditions imposed, the ultrasonic vibration boundary conditions were made approximation. The residual stress of SiC/316L composite coating with ultrasonic vibration in laser cladding was investigated, and the influence of ultrasonic amplitude and scanning speed on residual stress of composite coating was studied. According to the optimization results, SiC/316L composite coating was prepared by ultrasonic aided laser cladding.The results show that ultrasonic amplitude and scanning speed have significant effects on x-stress, y-stress, shear stress at the interface and von Mises stress on the coating surface. The residual stress relaxation of SiC/316L composite coating is excellent when the ultrasonic amplitude is 10 μm and scanning speed is 10 mm/s. The structure of coating is obvious refinement, and SiC particles is uniform distributed for the ultrasonic cavitation or mechanical effect and acoustic streaming effect.