Abstract: The precision optical chopper is used to chop and modulate incident light at the spectrum measurement, so as to realize the detection of weak optical signal.The chopping stability, anti-interference and accuracy of chopper controller are the key factors that can affect the detection effect. The existing optical chopper controller mainly adopts closed-loop control strategy of PID, leading to the anti-interference and accuracy are limited. In order to realize the high precision control, the fuzzy PID control strategy is used to improve the precision optical chopper control system, and the fuzzy control is combined with PID control. The Simulink simulation results show that, comparing with the traditional optical chopper, the precision optical chopper with fuzzy PID control strategy has better speed regulation performance and speed ability.