In order to solve the problem that the wear of H13 die steel affecting the die service life,the process of laser cladding Ni-based coating on H13 die steel was simulated and analyzed using finite element analysis software.In the laser cladding process,two heat conduction processes,rapid heating and rapid cooling were experienced,and its cladding temperature can reach up to 1551 ℃. At the same time,the influence of different coating thickness on the temperature field was investigated,and the thicker the coating,the lower the temperature. In the laser cladding process,the welding residual stress on the coating surface is mainly tensile stress,and the compressive stress is mainly on the substrate surface. The effect of different coating thickness on the stress field was also studied,and the thicker the coating,the greater the resid ual stress. It is verified by experiments tha t the temperature field of laser repair of die wear calculated by numerical simulation is close to the experimental value,and the cross-sectional view of the welding melting zone obtained by the laser cladding test is basically consistent with the simulation result. The actual melting zone width is 1.19 mm and the depth is 0.20 mm;the simulated melting zone width is 1.21 mm and the depth is0.21 mm. The simulation results of the laser cladding repair layer on the wear surface of the die are proved to be correct and the method is effective.