A light-weight design method was introduced considering the constraints of the space layout,function,strength,manufacturing and strengthening processes of the constant velocity universal joint drive countershaft.The shafts designed based on this light-weight method can meet the requirements,which was verified by static strength and fatigue tests.Besides,its effect on weight reduction is much more clear than those of solid shafts,constant diameters hollow shafts and friction-welded shafts.