In this paper,the TIG welding technology is used to perform a plate welding test on 304 stainless steel,and the test results are analyzed from the microstructure and mechanical properties,the optimum welding parameters are selected as welding current of 310 A and welding speed of 13 mm/s.The composition of austenite and ferrite in weld microstructure of welded joint is obtained by metallographic characterization,X-ray fluorescence diffraction and electron backscatter diffraction. According to the optimum welding parameters,the large-scale finite element simulation software ABAQUS is selected,and the TIG welding process is simulated by double ellipsoid heat source model. The weld cross-section morphology obtained by simulation and test are compared,and according to comparison results,the simulation model is optimized to provide reference for the optimization of welding parameters.