By analysis of tooth profile of chain wheel machined with form milling cutter in our company, an improved design of form milling cutter and the application result after improved are introduced.

This paper analyses the geometrical character of curve of edge of form milling cutter, and infers the mathematical equations of curve, The center coordinates of conical button-shaped are evaluated.

By mathematical calculation and using a copying fixture, the orbit of movement of an end-milling form cutter is obtained.