Referring to the problem of true-fake warhead recognition in missile early warning satellite system,a new algorithm of warhead target recognition for decision-making system is established. By use of some infrared attributes as characteristic parameter of warhead target recognition, such as temperature change rate, thermal capacity difference, radiant intensity, gray characteristic and infrared movement characteristic, information fusion based on the Analytic Hierarchy Process (AHP) algorithm of multiple attribute decision making is applied. Furthermore, fuzzy dynamic method is applied to construct the attribute importance estimation matrix, and the problem of the attribute weights being changed with time is efficiently solved. The true warhead is recognized by the result of fusion and ranking. The simulation results show that this target recognition algorithm is trusty and practical.