In order to improve the detecting precision on the position of time grating turntable control system, this paper proposed a fusion control method of kalman filtering and PI controller, and design a control system. The predicted selfadaption of the PI controller is achieved using the Kalman filter prediction, the control system to realize the a fusion control method of kalman filtering and PI controller by adopting the double closedloop control structure including current loop as inner loop and position loop as outer loop, regarding the time grating sensor as turntable displacement feedback components, using ARM (LPC2124) as the control core, and. the hardware incuding the power supply circuit, sp3232 serial communication, etc. Experimentation indicates that the time grating turntable servo system is stable and reliable and the accuracy of the position varies from 0.8″to 1.2″, which meets the requirements about the accuracy of the high precision time grating turntable control system.