Numerical control machine tool is a mechanical and electrical integrated processing configuration with high technical integration and automation, and it is a product that comprehensively applies high-tech skills such as planning machine, active control, active detection and precision machine. With the growth and popularization of CNC machine tools, the demand for skilled talents who know both CNC machining skills and CNC machining programming will continue to grow. CNC lathe is one of the most widely used CNC machine tools. In this paper, the step style in NC lathe parts processing is discussed.