Situation assessment (SA) is a complex decision-making process in modern aerial defense system. Threaten ordering
(TO) problem is one of the most difficult steps in SA. There are a lot of uncertain factors in TO, and traditional
evaluation methods have some disadvantages on algorithm measures. To overcome these disadvantages, a method of TO
based on cloud model theory is proposed. Firstly the factors of air-targets threat evaluation are analyzed in this paper.
Then the reasoning mechanism base on cloud model is designed. In this step the cloud model is used to depict the
attributes of target, the model parameters are defined, and the reasoning rule library is established by using the method of
Multiple Attribute Decision Making (MADM). The data of targets were input to the reasoning mechanism, and the threat
value was gained. Finally the simulation experiments are given to verify the validity of the method.