Abstract: The residual stress of the girth welded joints of L360 pipeline under different post-weld heat treatment conditions was measured by hole drilling strain-gauge method, and the tensile test, hardness test and microstructure analysis were carried out for the girth welded joints under different conditions. The results show that the residual stress of the girth welded joint can be significantly improved by heat treatment in 550-670 ℃. The axial and circumferential stresses decrease significantly, and the circumferential residual tensile stress decreases by 74.5% compared with that of the welded joint. After heat treatment, the hardness of L360 girth welded joint decreases slightly, but the hardness distribution is more uniform and the softening problem of heat affected zone is improved. The heat treatment can reduce the tensile strength of L360 girth welded joint slightly, but it will not affect the original strength match relationship.