The assessment of the extent of threat from an air raiding target, as one of the key problems in the decision of air defense command, involves many uncertain factors and some other unknown factors which will make the information available insufficient for the decision - maker to determine all the attributes of the air target. Therefore, by employing Dempster/Shafer Theory of Evidence (DST) to deal with ignorance and incorporating Analytic Hierarchy Process (AHP), the method for threat sequencing based on partial unknown attribute value is presented. In addition, an example is applied to show the method.