Abstract: To support the infrared air–air–missile development of medium and long ranges, an estimation method for the infrared seeker detection range is proposed. Lock-on-after-launch technology is employed. It is based on an "information binding and scene model". The method is based on the classical theory of infrared system performance estimation. Through the analysis of the environmental characteristics of the air battlefield, the information binding requirement from the aircraft or control system is completed. An estimate scheme block diagram and an example for engineering applications are given. The results show that the method can give distance estimation results that match the real-time situation, and it has the advantages of a small data scale, fast query speed, and minimal calculation steps. The method addresses real-time application needs under limited resources.