This paper presents an electronic subdviving method for linear encoder of high speed position detection. The method aims to enhance the resolution of position measurement and improve the precision of noncircular component cutting system. A 20-subdividing circuit based on resistor chain phase shift is researched and implemented, and some key technologies are discussed. The method is proved to be successful in raising the resolution and precision with a high speed response. The experiment result proves that electronic subdividing method is doable and effective to raise the resolution of the existing system.