In order to improve the automatic production level of NC cutting machine,a scheme of NC cutting machine processing system was designed.Based on the key technical points such as the motion speed control and trajectory interpolation algorithm of NC cutting machine,according to the data characteristics of HPGL protocol,the CNC machining data generation method of NC cutting machine was proposed,a speed control method based on segment segmentation was designed to generate the speed list,and the host computer was developed based on Microsoft foundation classes(MFC) to realize the function of processing the motion speed control of each segment in the curve.The application method of combining machining interpolation algorithm with data stack was designed,and the lower computer was developed based on STM32F103 to calculate the interpolation step of each line segment and control the trajectory.Through the sample test,it is verified that the designed NC cutting machine system has the feasibility,efficiency and accuracy of actual processing,and can effectively meet the needs of production.