Abstract: This paper presents a CAD/CAM system for free form surface of relief,called DMR system,which uses a modularized idea for designing a program.Every modularization is independent,and transmits messages with the database.In creating the mould surface,a great many calculation can be simplified by combining PB spline and Bezier theory organically.In calculating the path of the cutting tool,the simple and quick Bezier surface dispersion method is used.It improves the calculation speed and precision.The whole system can be debugged on microcomputers.