Based on the finite element software ANSYS, the welding process of bipolar stainless steel 2507 pipe by tungsten inert gas (TIG) welding was simulated. APDL command was used to divide the finite element model of duplex stainless steel 2507 pipe into different grids in different regions. The element birth and death technology were used to simulate the filling process of weld material. The uniform body heat source model was applied, and the weld element was gradually activated with the movement of heat source. The transient analysis was carried out to obtain the temperature distribution under multiple working conditions. The temperature field contours of the model under different load steps are viewed in the post processor, and the temperature curves of the typical position nodes in the welding process with time are viewed in the time history processor. By comparing the temperature field nephogram and temperature variation curve under different welding speeds and welding currents, the optimal welding process parameters in this group were obtained, which provided certain theoretical help for the analysis of actual welding process.