Aiming at the application of the 8~12 μm band infrared detection system used for the ground or low altitude target imaging and identifying in cloud and rainy weather,taking the experiment location as the reference point,the simulated experiments are carried out for the environment of clearness atmosphere and cloud rainy weather by PcModWin atmospheric simulation software.The distribution curves of infrared radiation transmittance and the variation law of peak parameters in a certain distance range under different conditions are analyzed.Compared with the real infrared target image,it is proved that some parameters are the main factors affecting the application effect of infrared detection system in this band,such as the detection angle,atmospheric visibility,rainfall intensity,cloud type,etc.,and the strategy methods are put forward which should be taken in engineering application.Application results show that the conclusion of the research has general engineering significance,and plays an important role in the war application of the infrared weapon system in this band.