Infrared decoy is one of the most common interference equipment in infrared countermeasure, which intends to delude and interfere with infrared guided missile for hiding the truth and giving a false impression. The mechanisms of infrared decoy interfering with infrared guided missile were analyzed. The moving and radiation models of airborne infrared decoy were built. According to the interference shortage of airborne infrared decoy, a combat operational method of infrared decoy was obtained. The method was able to synthetically take into account many factors such as different interfered missiles, dispensing time, dispensing direction, dispensing number, dispensing interval time and fighter′s elusion. The combat operational method provides a basis for fighter against infrared guided missile, so that to perform airborne infrared decoy′s combat effectiveness completely and enhance fighter combat survivability.