With the development of modern manufacturing technology, the requirements for machining accuracy of mechanical products continue to improve, and numerical control machining occupies an important position. More and more products with complex structure and traditional processing methods can not meet the production requirements need to be processed on CNC machine tools. The common CNC machine tools are CNC lathes, CNC milling machines and machining centers. This series of courses mainly introduces the simulation and actual processing of CNC lathes and milling machines. Take the parts in production practice as an example, formulate the processing technology, compile the program, and finally simulate and process the finished products.