To improve the detection performance of dynamic object tracking system that cannot work normally at night, the infrared detection technology is put forward to design and study its detection tracking system. According to the characteristic that projectile can produce heat radiant energy when it flying, the surface projectile was divided into small unit area independently to calculate its infrared radiation energy, its heat radiation temperature equations were established, the method of four-order runge-kuta was applied to analyze and calculate temperature parameter. The relation between atmospheric attenuation and detection performance was analyzed in dynamic object tracking system. Through calculating and analyzing, the theory of infrared radiation technology meets the need of dynamic object tracking system.