Abstract: Aiming at the different characteristics between the detection information of infrared search and track (IRST) system and the radar detection information of friend aircraft transmitted by laser data link system in cooperative air combat, an asynchronous information fusion method based on optimum data compression was put forward to improve the capability of detecting system. The information fusion processes, including time registration, space alignment, data fusion and target tracking, were analyzed. Beside, the observation curve, real contrail and error curve before and after fusion were respectively contrasted and analyzed. The errors of azimuth angle and pitch angle were kept within 2mrad after fusion. Result shows the method can improve the data precision effectively.