In view of the complexity of the traditional method in flying distance computation, a method based on self-adaptive fuzzy logic system is put forward. A fuzzy model of flying-distance computation of a certain airplane is set up by using the fuzzy logic method and its parameters are identified by the error-back propagation algorithm and the least square algorithm. The experiment result shows that the model has the advantages of faster rate and higher identifying precision, and can be used in flying distance computation of a certain airplane.