In this paper, a novel comprehensive fault identification approach was proposed based on the harmonic window decomposition (HWD) frequency band energy extraction and grey relation degree. Firstly, in order to eliminate the influence of noises, the line structure element was selected for morphological filter to denoise the original signal. Secondly, due to the energy of vibration signal will change in different frequency bands when fault occurs, therefore, the six feature frequency bands which contain the typical fault information were extracted by harmonic window decomposition that need not decomposition; and the energy distribution of each band could be calculated. Finally, these energy distributions could serve as the feature vectors, the grey relation degree of different vibration signals was calculated to identify the fault pattern and condition. Practical results show that this method can identify rotor fault patterns effectively.