The fatigue life and also the welding residual stress of the welded tubular X-joints are investigated experimentally. Furthermore, some joints are shot peened and the effect of shot peening on fatigue life of these joints is explored. The results of experiment show that the fatigue life of shot peened tubular joint is about twice of the original tubular joint. Cracks are initiated in all cases at weld toe. The in depth residual stress measurements on the joints, before and after the fatigue loading, show that fatigue loading causes the relaxation of residual stress created by welding and shot peening. The level of the residual stress on the surface is reduced to half of the original value
