Abstract: Harmonic wavelet transform(HWT)is applied to the vibration analysis of a cracked rotor bearing system with rubs of its stators and rotors. Three nonlinear factors are taken into account. Using the time-frequency maps of HWT, the characteristics and energy distribution of rotor system can be described in detail. And the effect of the three nonlinear factors is investigated. Result shows that the nonlinear oil film force can weaken the faults characteristics, and the effect of the crack and rub-impact force must be considered simultaneously. In addition, the multi-nonlinear factors should be taken into account in both time domain and frequency domain to detect the faults of rotor bearing systems.