The residual stress of the welding joint of S355J2W+N steel was studied in this paper,and the residual stress distribution of weld seam was analyzed. The results show that the longitudinal stress and maximum principal stress of the weld area are mainly tensile stress,which decreases the trend from the center to the edge. The lateral stress of weld area is dominated by compressive stress,and the maximum value（absolute value）appears at the edge of the specimen. The residual stress is compressive stress,and the maximum value（absolute value）appears in the intermediate region of the weld and the edge of the plate. The residual stress difference between the repaired and unrepaired joints was not significant,without obvious regularity. Through the experiment,combined with the existing research conclusion,for the stress after welding butt joint structure with the annealing treatment,residual stress has little effect on mechanical properties of welded joint.