Because the spaceborne atmospheric composition limb detection spectrometer needs to use the reflection of the reflector when collecting the optical information in the height direction, in order to meet the scanning requirements of the spectrometer, a scanning pendulum mirror drive control system is designed, and the spectral data acquisition in the scanning direction is simulated and verified on the ground. The designed drive control system is basedon STM32 microcontroller. DRV8833C motor drive circuit and closed-loop digital PID regulator are adopted in the system, a finite rotation angle DC brushless torque motor is used as the actuator of the spectrometer swing mirror control system, and an 18-bit single-turn absolute value photoelectric encoder is used as position sensor. Then the swing mirror control system and test platform are built, the performance of the swing mirror system is verified by the photoelectric autocollimator, and the pointing accuracy of the system is tested. The results show that the average pointing accuracy is less than 12.15'', the maximum deviation is less than 19.6'', and the minimum deviation is less than 7.46'', which meets the requirements of the main indicators in the pre-research stage of the project.