Aiming at the serious image distortion of elliptical orbit infrared surveillance system and the low precision of target confirmation algorithm based on image registration, a novel target confirmation method based on line of sight (LOS) vector sequence is proposed. By establishing the state transition model and observation model of target LOS vector sequence, the GM-PHD filter is used to filter LOS vec-tor sequence data and confirm target. Owing to that the GM-PHD filter will lose the new target when its states are unknown, the feedback GM-PHD filter is proposed. The simulation results verify the effective-ness of the proposed method based on LOS vector sequence and the timeliness of the improved GM-PHD feedback filter for new target states estimation.