Abstract: The experiments were carried out on titanium alloy through helical milling and traditional drilling processes,and the holes quality and the influence factors were investigated.Results show that,comparing with the traditional drilling,the helical milling showed better hole quality and the smaller surface roughness.For helical milling process,the axis feed per tooth was the main factor on surface roughness of the holes,the transverse feed per tooth was the main factor on the holes roundness,but the holes diameter was not significantly affected by the helical milling parameters.For traditional drilling process,the axis feed per tooth was the main factor affecting surface roughness,roundness and diameter of the holes.