Abstract: High-speed milling of aluminum alloy is one of the important application areas of high-speed cutting technologies. Selection of high-speed milling tools is an important problem, which many enterprises are now facing during manufacturing practice. This article mainly deals with the optimization of the selection of the high-speed milling tools on the basis of studying the cutting forces. The materials, rake angle and brand of the cutting tools have been selected as the three tools by using method of comprehensive ambiguity judgment.