With the rapid development of CG technology and 3D scanning technology, it is easy to design the freeform surface more complexly, but it also makes it difficult to machine such complex freeform surface rapidly and accurately. In this paper, a tool path planning assist system for freeform surface machining is presented. Differing from general CAM systems, in this developed tool path planning assist system, the tool path is generated based on the features of the CAD model, and focus on the applicability of material removal process. New machining strategies for both rough cutting process and finish cutting process are presented. With the assisting of this developed system, freeform surface could be machined efficiently and accurately.