Recently, for enhanced productivity the induction of CAD/CAM is vigorous. Most of high-level CAD/CAM systems produce powerful faculties. But it is very expensive to purchase the system in small and difficult to be operated by non-experienced workers effectively. Then the resonable CAM system for these is needed. In this study we developed a proto-type of the CAM system for CNC lathe connecting with personal computer. This system is configured with interactive menu windows for easy control of CNC lathe. And the system supports tool path generation for cutting conditions of workpiece. The performance of this system is satisfactory.