For meet the needs of LK6804A machining’s CNC transformation, we designed a numerical control system for the machine. Use the Germany's Siemens 840D CNC modules and other spare parts, integration and realized two axes feed control machine functions, and PLC realized switches control, the CNC and the DMS control act as monitor together. The system was used in the factory. The result shows that the design is feasible and practical, and activated the machine and the system functionality, highly cost-effective.