Abstract: The finite element model of SiC/316 L composite coating was established. The boundary conditions with ultrasonic vibration was made approximation by the method of combining thermal effects conversion with dynamic boundary conditions imposed. The temperature distribution and residual stress of SiC/316 L composite coating by ultrasonic-assisted laser cladding were discussed. The influence of ultrasonic amplitude and scanning speed on the temperature field and stress field were investigated. The results show that the surface temperature of coating is increased with the decrease of ultrasonic amplitude and scanning speed. The residual stress of coating is reduced with ultrasonic vibration. With the increase of ultrasonic amplitude and scanning speed, the residual stress reduces firstly and increases afterward. The experiment of ultrasonic cladding is prepared by the optimized technological parameters. The test results show that the microstructure of coating are refined and uniform with ultrasonic vibration, which is conducive to reduce the residual stress of coating.