In the field of modern national defense and military industry,photoelectric systems are widely used in in fire control,reconnaissance,guidance and other weapon systems. With the improvement of target maneuverability,the demand for dynamic performance of servo system for photoelectric weapon systems increases,and the bandwidth of photoelectric servo system has to be expanded. However,the inherent characteristics of the mechanical resonance do not change and the driving energy close to or exceed the nature mechanical resonance frequency does cause mechanical resonance. In order to improve the performance of photoelectric servo system,the detection and suppression of mechanical resonance needs to be studied. Firstly,through the analysis of the characteristics of the stimulus signal,the stimulus signal with excellent characteristics and low calculation is selected to identify the parameters of the mechanical resonance of the photoelectric servo system,and then a parameterized notch filter is designed for online parameter adjustment,which can realize a rapid and effective suppression of mechanical resonance on photoelectric servo system. The experimental results show that the scheme of mechanical resonance detection and suppression can accurately detect the mechanical resonance frequency,well suppress the influence of mechanical resonance and improve the dynamic performance of photoelectric servo system.