In this paper, the current state of Open-Architecture CNC system at home and abroad is investigated, the advantages and disadvantages of system architecture and developing platform in prevalent numerical control system is discussed, Windows CE.NET is chosen to be the soft-developing platform of new numerical system, and the reason why such platform is superior to others is introduced. The main content of this paper is the key technologies of real-time control of CNC system based on Windows CE.NET.The operat...