In order to study the vibration response characteristics of bearing system with local damage, a dynamic model was developed based on multibody dynamics to predict the size, location and shape of local defects of the bearing, and the influence mechanism of defect parameters on bearing vibration was analyzed. The result shows that the vibration response of the bearing increases gradually with the increase of defect size. As the position of the defect moves away from the maximum bearing area, it will gradually decrease. The vibration response of the rectangular defect is the largest, triangular defect the second, and circular defect the smallest. The relationship between the vibration response of the cylindrical roller bearing and the size and location of local defects is obtained through a bench test, and the reasonableness of the dynamic analysis are verified by comparing with the simulation results. It will provide a theoretical reference for diagnosing the early failure mechanism of bearings.