This paper is to provide a reasonable means to approach tool shape optimization of ball end mill for high-speed milling operation. The paper presents a new development of an integrated system for ball end mill design, creation and evaluation that is more flexible and more systematic than the commercially available tool fabrication systems. The study consists of three major contents: (1) 3D-CAD/CAM system development for ball end mill design and creation, (2) fundamental investigations of cutting characteristics with different ball end mills, and (3) improvement of tool life and machining stabilization for high-speed milling by means of new tool shape proposals. These are explained in the following sections, respectively. Through the above developments and investigations, it is evidently found that the developed system shows great validity and possibility to realize tool shape optimization of the ball end mill.