The basic concept and process of information fusion are introduced based on the JDL information fusion model. Then, a method for airborne multi-sensor information fusion composed of a whole set of algorithms is given, including the algorithm for space-time alignment, data association, composite tracking, and state estimation. Suggestions are presented for the engineering application of the algorithms. The simulation results show that the proposed fusion method can guarantee the timeliness of multi-sensor information fusion, and has high correct association rate and state estimation precision, which can satisfy the requirements of engineering applications.