Abstract: In order to make the liquid metal distribution of TIG welding pool more uniform, the influence of welding torch swing on the behavior of weld pool is studied based on ordinary TIG wire-filled welding. The mathematical model of TIG wire-filled welding for welding torch swing is established, and the tracer particles are utilized. The method compares the temperature field, flow field and droplet mass distribution of ordinary TIG wire-filled and swing TIG wire-filled. The analysis shows that the ordinary TIG wire-filled weld pool profile is basically the same as the swing TIG wire-filled weld pool, but the swing TIG welding changes the flow field behavior in the weld pool by swing arc, which affects the distribution of temperature field and makes the temperature distribution in the weld pool more uniform. The tracer particles distribution shows that in TIG wire-filled welding, the swing TIG wire-filled welding can make the droplet metal more evenly distributed in the weld pool.