According to the high development cost and high power consumption problems of CNC system of plate bending machine based on industrial control computer and PLC or motion control card, designed an embedded CNC system based on ARM and CPLD. Using S3C2416 and EPM570T144C5 as the main control chip, and the design of hardware, CPLD program and software of the CNC system was introduced in detail in this paper. Through experiments and simulation of the system, the results showed that the system has good stability and reliability. The system can be flexible in handling different interface modules, with small volume, low power consumption, and can be applied to three or four roller bending machine or other industrial control applications.