Abstract: Dissimilar Al alloys of 5083 and 6082 Al alloys were welded by friction stir welding (FSW) with butt joint. With short-wavelength X-Ray diffractometer (SWXRD), measuring directions of residual stress for 311 and 111 crystal planes were respectively determined by analyzing the outmost circle data of pole figures. Then, welding residual stress of center layer in FSW plate was investigated by d₀ method. The results show that the longitudinal stress distribution on 311 crystal plane is similar to that on 111 crystal plane, while the two peak values of tensile stress appear in weld zone. Compared with 311 crystal plane, the measuring data on 111 crystal plane are more scattered. There is a relatively large difference of transverse residual stress between 111 and 311 crystal planes.