In order to process the nonstationar y vibration signals during speedup and speeddown of a gearbox, the order cepst r um technique and the empirical mode decomposition(EMD) methods were presented to diagnose the rolling bearing. This method combined the order tracking technique with the HilbertHuang transform. First , the vibration signal was sampled at a constant time increment and resampled a t a constant angle increment. Therefore, the transient time domain signal was changed into pseudostatio nary angle domain one. Se cond, the signal in angledomain was analyzed with EMD. At last, the high fre q uency intrinsic mode function(IMF) component, which contained the fault informa tion of the bearing, was studied with the order cepstrum analysis and the fault character of the bearing was extra cted. The experimental results show that combining the order cepstrum analysis w ith the EMD techni que can effectively determine the positions and types of bearing faults.