Abstract: In order to solve the problem of undercut and hump defects during tungsten inert gas (TIG) welding of TA2 thin-walled straight pipe, the laser-TIG arc hybrid welding process was conducted. For TA2 straight welded pipe with size of 准19 mm 伊0.7 mm, use different heat source models for single TIG self-welding and TIG arc assisted laser welding, the Abaqus software was used to establish welding finite element model, and the temperature cyclic curve during the two processes and postweld residual stress were comparatively analyzed . And the microstructure analysis and mechanical property test of the TA2 thin-walled pipe obtained by experiment were further carried out. The results show that the contour sizes of the simulated two joints are similar to the actual joints. The weld center temperature and the postweld Von Mises stress of TIG arc assisted laser welding are lower than that of TIG welding. Compared with that of TIG welding, the microstructure of the weld center and heat affected zone of TIG arc assisted laser welding is smaller, and the tensile strength and elongation are basically unchanged, and the yield strength is higher. High weld quality can be obtained by using arc assisted laser welding with TIG arc in the front under the condition of good weld forming.