Rolling element bearings are widely used in rotating machinery, and are usually the weakest components that affect the operating reliability of machines. In this paper, a quasi-static model of rolling bearings based on Jones′ bearing theory is proposed. By integrating the bearing model with the finite element model of a rotor, a dynamic model of the rotor-bearing system is obtained. For bearing defects modeling, a series of approximately equally spaced force impulses are generated. The generated force is input into the dynamic model of the roto-bearing system, and then the vibration responses are calculated using the Newmark-β time-domain integration method. The simulated vibration responses of defective bearings are compared with the measured data from a bearing test rig. The results show that it is feasible to predict the vibration response caused by bearing defects with a theoretical model, which may provide useful proofs for fault diagnosis of rotor-bearing systems.