Abstract: Aiming at the difficulty in extracting the characteristic frequency of impact faults when the gearbox is faulty, a method based on adaptive Teager energy operator (ATEO) is proposed, which can improve the signal-to-noise ratio and highlight the characteristics of gear failures. Employing this method, the kurtosis of signal can be enhanced by 1 time and the impulsive features are highlighted. Moreover, it is applicable to monitor and diagnose the gear faults with simper calculations.