The servo mechanism of satellite-borne two-dimensional turntable is a kind of high-precision pointing adjustment mechanism.At present,the motion frequency band of on-orbit is 1Hz~300Hz,and the stepping motor has vibration problem when rotating at low frequency. In order to solve this problem,this paper proposes a subdivition method for controlling stepping motor based on SPWM, FPGA is the system control core,and combines the motor driver chip LMD18200 to form a complete motion control platform,which realizes the subdivision control of SPWM stepping motor. The simulation by modelsim and practice show that the motor can run smoothly at low frequency,effectively reducing the noise of the motor during starting and stopping ,and the vibration of turntable during rotation is obviously reduced.