Abstract: In order to solve the problem of lage welding deformation of 06Cr18Ni11Ti austenitic stainless steel sheet,pulse TIG welding was used for the T type welding. The structure of welded joint was analyzed. And the welding stress and deformation were simulated by using a generalized double ellipsoid heat source. The results show that the structure of the molten pool is vermicular and dendritic fine austenite, and the grain size of the heat-affected zone is not bigger than that of the parent material. The structure of welded joint is well. The residual stress after cooling is concentrated and basically in the weld area. The overall deformation of the welded part is minimal. The deformation mainly shows the z direction（vertical direction）contraction of the weld and vertical plate, and the angular deformation around the x axis（weld direction）