Abstract: With the characteristics of the 4^th generation fighters and modern air-combat included, an improved hierarchical architecture model of the air-combat capability was put forward, and combined with the analytic hierarchy process and fuzzy membership function technique for the static evaluation of the air-combat effectiveness. Moreover, the sensitivity of the air-combat effectiveness to each single item at the lowest level and all the items at the same level was defined and formulated. Two typical fighter examples, denoting for the 3^rd and 4^th generation fighters respectively, were used to demonstrate the rationality of the model, and the sensitivity analysis shows to be able to provide guidance to fighter upgrade and aircraft combat operation.