In order to investigate the influence of laser shock processing on the residual stress distribution of stainless steel welding joint, the numerical analysis of the stainless steel welding process and laser shock processing weld is implemented. The results show that the residual stress distribution of welded structure is not uniform after welding, and the large residual tensile stress is produced on welding surface, meanwhile, the differences of welding residual stress between horizontal and vertical orientation are large. The residual stress of welding area is notably improved after laser shock processing, the residual stress on surface is changed from tensile residual stress into compressive residual stress, and the residual stress increases with laser power density and shocking times increasing. The residual stresses on horizontal and vertical orientation become uniform. The uniform residual stress can be induced with suitable overlapping rate. It provides a reference for the application of the laser shock processing in improving welding structure performance.