Based on an in-depth study of wavelet gray moment,we proposed a concept of a time-division scale level moment and gave the specific definition;ulteriorly,we discussed the factors which affeaed the fault diagnosis abaity of a time-division scale level raomert.The analysis results in the caculatiort of six typical fault signals show that the time-divisiort scale level moment can be used to display the detailed information of a wavelet gray level image,extract the signals characteristics effecavely,and diatinguish the vibration fault.Compared to the method of a wave gray moment vector,the method mentioned in this paper can provide higher calculation speed and higher capacity of fault identification,so it is more suitable for online fault diagnosis for rotating machinery.