Aiming at the difficulty of forming high strength aluminum alloys by selective laser melting technology, this paper conducts finite element analysis based on ANSYS software to study the selective laser melting of aluminum alloys, and reveals the temperature field distribution and basic characteristics during the forming process. And the temperature gradient of the scan track is studied through the temperature distribution cloud map. At the same time, the influence of laser power and scanning speed on the thermal behavior of the molten pool was studied, and the influence of the scanning process parameters on the shape of the molten pool was studied by means of simulation. The results show that in the simulation forming process, the size of the molten pool has a nonlinear relationship with the scanning speed, and is positively related to the linear energy density of the laser input. As the energy density increases, the size increases. The simulation results are verified by experiments, and this study can provide a theoretical reference for subsequent forming analysis.