The high-speed steel milling cutter type are very many, the consumption is also very big, is mainly because some end mill's quality is bad. We use the general end mill is mostly buys from outside, the special-purpose end mill is this factory production. Through may know to the special-purpose end mill damage way's analysis, some 45% end mill for the early endurance failure, its fracture's position are in mostly the crater nearby R angle place. This indicated that end mill here anti-fatigue failure ability is low, causes the butt welding end mill's early damage.