Abstract: The axial and circumferential residual stress distribution of welded joints of P91 pipeline along the thickness direction was quantitatively measured by the contour method, and the influence mechanism of bending moment on the stress distribution was determined. The residual stress of circumferential welding measured by the contour method was reconstructed and corrected, which made the corrected results more realistic. The finite element model conforming to the actual situation was established, and the distribution law of welding residual stress along the thickness direction was defined. The results show that at the center of the weld seam along the thickness direction, the circumferential welding residual stress generates a distribution trend of decreasing first and then increasing from the outer surface to the inner surface, and all are tensile stress distributions. The circumferential welding residual stress on the inner and outer surfaces is significantly greater than that at the thickness center, the minimum circumferential welding residual stress occurs at the thickness center. The residual stress in axial welding shows a distribution trend of gradually decreasing compressive stress to tensile stress from the outer surface to the inner surface, and the tensile stress reaches its peak at the thickness center.