The order tracking technique and TeagerHuang transform (THT) approach are applied to gearbox fault diagnosis during runup. Firstly, the stationary s i gnal in angle domain was obtained by evenly resampling the vibration signal that had been sampled synchronously in the time domain. Secondly, the angle domain s ignal was decomposed into the intrinsic oscillation modes by using empirical mode decomposition (EMD). Thirdly, the Teager Kaiser energy operator (TKEO) techniq ue was applied to each intrinsic mode function (IMF). TKEO can track the modulat ion energy and estimate the instantaneous amplitude and instantaneous frequency.In the end, the timefrequency distribution was obtained according to which the bearing fault features were recognized. The experimental results show that the order tracking and the TeagerHuang transform can effectively diagnose the bear ing faults.