Abstract: In order to investigate the manufacturing performance of maraging steel by laser cladding, 18Ni300 powders and substrate were selected for simulation analysis, and the influence of different process parameters on the temperature field during the manufacturing process were studied, the experimental results were verified and analyzed. The results show that the maximum temperature curves have the same trend under each process parameter, and the influence of laser power is more significant for the rapid increase and the stability at a certain time. The cladding layer is formed with the laser movement, and the front end is formed when the laser is not reached. Compared with the terminal, the front end has larger temperature gradient, and the shape of the melting pool is spoon-shaped. The temperature in the scanning direction reaches the peak from slow to fast, and the temperature at the later point is greater than the previous point. The temperatures in the vertical direction all reach the peak at the same time. The greater the power, the greater the temperature gradient. The simulation results are in good agreement with the experimental results. Based on the analysis of the formation causes of solidification parameters, the optimal test parameter is obtained. It saves the test time and cost, and has a guiding role in the analysis and selection of the test results.