Abstract: Irregular typewriter knocking noise caused by the oil film cavitation of the engine main bearing has been an unsolved problem in the automotive field. In order to study the irregular cavitation noise of main bearing under the coupling effect of engine spindle bearing dynamic load performance, the experiments were carried out in the oscillatory parallel-plate squeeze film test apparatus which can simultaneously collect five kinds of signals including vibration acceleration, displacement, sound pressure, force and pictures of cavitation. The effects of excitation signals, extrusion amplitude, extrusion frequency, and viscosity of the lubricant on the cavitation noise characteristics were investigated experimentally. The experimental results showed that it was easy to generate cavitation noise under square wave, a large amplitude, a high-viscosity lubricant, and a pressing frequency of 12 Hz.