Abstract: The deeper research has been made in this paper on reverse engineering of cam mechanisms with oscillating cylindrical roller followers．A novel solution has been given that a new cam contour is designed analytically using both the structure’s parameters and the follower motion which is a reverse solution using measuring data of the original cam contour based on the theory of conjugate surface．In this paper，the reverse engineering methods and measuring data are analyzed first．Then，some corresponding properties of cam contours are given ．Based on that，a non-linear mathematical programming model is derived and its solution is studied．At last，CAD of cam mechanisms with oscillating cylindrical roller followers based on the method proposed is discussed．The reverse method presented here can also be used in the cam contours’ verification．