Abstract: A new rotor-ball bearing-stator coupling system,including imbalance-misalignment-rubbing coupling fault,was established for aero-engine vibration.In the coupling system,the stator motion was considered,and the nonlinear factors of ball bearing such as the clearance,nonlinear Hertzian contact,and the varying compliance(VC),were fully taken into account;in the process of fault coupling,the imbalance,the misalignment and the rubbing faults were modeled respectively.The numerical integral method was used to obtain system's responses,and the characteristics about the coupling faults were analyzed.The simulation results indicate the correctness and effectiveness of the new model.