Abstract: The conducting tube was studied with emphasis on the effect of the conducting tube′s shape and size on the breaking strength and anti-striping of the spun yarn through designing,experiments and analysis of the conducting tube.The results showed that the spun yarn has better strength and anti-striping property when the conducting tube undersurface′s length is 43 mm,the entrance′s heght is 30mm,the exit′s height is(24 mm,) the angle of the conducting tube undersurface and entrance side is 30°,the conducting tube exit′s width is 9 mm,the angle of the conducting tube upper side and entrance side is 148° and the conducting tube entrance′s width is 22 mm.