For the additive manufacturing processing of Laser Metal Deposition (LMD) technology, simulation is used to obtain the variation of each parameter with time during the processing. The three-dimensional model of the part was established by UG software, the finite element simulation pre-processing was carried out by HyperMesh software, and the additive manufacturing finite element simulation model was established by using Simufact. Welding software analyzes the temperature, deformation, and equivalent stress of the material in the scanning process of the laser Gaussian heat source, and finally analyzes the deformation and stress distribution of the part after cooling. The results show that the uneven wall thickness of the part or the thin wall that appeared due to slicing will lead to a drastic temperature change, and deformation increases, thus affecting the distribution of stress. The influence of the laser on the formed part is mainly located in the first few scanning cycles, and the degree of influence can be reduced by adjusting the setting of reasonable parameters.