Abstract: In order to cut the tooth surface of spiral bevel gear with spherical involute tooth profile which has no theoretical errors,we take the tooth surface generating line as the cutting edge.This method is base on the theory that the trace of circular arc on the tangent plane can form the conical involute hilicoid when the basic cone of spiral bevel gear rolling on its tangent plane.The movements that this kind of generating cutting method needs have been analyzed,and the method to realize the movements have been elaborated.The results indicated that the movements and the structure of the machine tool,and the cutting tool are very simple by using this cutting method.Moreover it can complete roughing and finishing of the convex and concave surfaces of the spiral bevel gear by one chucking.Cutting of the bull wheel and the pinion,including the left-handed and right-handed gears can be completed by the identical machine tool and the same cutting disc.More important aspect is that the contacting zone of two engaging spiral bevel gears is very easy to adjust.