Abstract: In order obtain engine mission profiles from a vast amount of flight test,the fuzzy matrix of the membership function of engine mission profile samples is established according to the theory of fuzzy sets and boolean algebra behaviours.The fuzzy matrix is examined by using sqaure method for meeting the equivalent conditions.When it meets equivalent conditions,the dynamic clustering is carried out by selecting various threshold values.The clustering analysis of the mission profiles for an actual engine has been completed by the complicated and enormous fuzzy caleulation based on statistical data of the engine loads measured in fiight test.The clustering method of three parameters(flight altitude,Mach number and angle of throttle lever)is first employed in the clustering analysis and the results abtained are satisfactory.