Abstract: Suspension discharge under strong vibration conditions is one of the important factors that induce the damage of oil-paper insulation in oil-immersed shunt reactors. In order to grasp the fault mechanism of suspension discharge inside the reactor and monitor the operation state of the reactor quickly and accurately, a test platform for suspension discharge defects of oil-paper insulation under vibration conditions was built in this paper. The influences of vibration amplitude and vibration frequency on suspension discharge were studied experimentally. The test results show that the larger the vibration amplitude of the iron core, the smaller the partial discharge; the order of the influence of different vibration frequencies of the iron core on the amount of partial discharge is: 50 Hz > 300 Hz > 200 Hz > 100 Hz. Based on the experimental results, the influences of vibration amplitude and vibration frequency on the maximum electric field intensity and oil flow velocity of the surface are simulated by means of finite element simulation technology. The simulation results show that the larger the amplitude, the smaller the maximum field strength on the surface, and the greater the oil flow velocity under the suspended electrode; the field strength and oil flow velocity at different vibration frequencies are arranged from large to small: 50 Hz > 300 Hz > 200 Hz > 100 Hz; based on the influence of oil flow velocity on oil flow charge and bubble motion in oil, the influences of field strength, oil flow charge and bubble motion on partial discharge are analyzed and compared. The mechanism of vibration amplitude and frequency affecting suspension discharge is discussed in detail.