Abstract: Aiming at the welding problem of an excavator bucket lug, the welding temperature field and the residual stress field of the key welding seam of the lug were calculated based on the MSC.Marc software. The influence of different welding sequence on the welding residual stress and deformation was further investigated. The results show that the residual stress in the weld area is relatively large, and the peak values of the longitudinal residual stress of the key welds of the lug are located in the arc section of the welds.The bottom plate welds have little effect on the residual stress of the lug weld, in order to simplify the model and reduce the amount of calculation, the influence of bottom welds can be ignored.While the welding sequence of the key welds of the lug has a significant influence on the residual stress and deformation. By comparing and analyzing the welding residual stress and deformation, the optimal welding sequence was obtained.