Laser cladding (LC) process is widely used in repairing and surface modification of machine parts. However, high residual stress and large thermal distortion are caused during LC process, resulting in lower fatigue strength of LC layer and deterioration of dimensional accuracy. In this study we developed 3D finite element models to perform LC repair process simulation especially SUS304 and SUS316L combination. The validity of the simulation results was verified by comparing with the in-situ measurement results, and it was found that simulation results showed good agreement with measurement results. It is likely that the numerical simulation enabled us to foresee residual stress and distortions during LC process, and help to optimize LC process parameter in order to minimize them.