Abstract: When the method of eddy current testing was adopted to detect a certain type of aircraft wheel hub, for the existence of cambered surface located at the detected part, this caused the difficulty of signal discriminate. Through a large number of the hub tested by the way of eddy current, the difference between the flaw indication and jamming signal was found. The results of analysis by using math function knowledge show that this recognition method can be more reliable in the use of detecting the signal of fatigue crack.