Abstract: In this paper, a numerical simulation model of oil-jet lubrication ball bearing was established based on volume of fluid (VOF), and a sliding mesh and multiple reference frame (MRF) methods were used separately to calculate and simulate its oil-air two-phase flow, obtaining the oil distribution inside bearing and the churning moment. Then, a visual test-bed was developed for the flow field of oil-jet lubrication ball bearing to analyze comparatively the simulated flow field and the experimental flow field captured by a high-speed camera. The results show that the oil volume fraction inside a bearing simulated by sliding mesh is larger than that by MRF, and the oil volume fraction can decrease gradually with rotation speed increasing. Under the centrifugal effect, the oil distribution is more focused on the outer race. Simulated with sliding mesh, the distribution of the flow field is closer to the visual result. The simulated churning moment increases with an increasing rotation speed, and the churning moment calculated by MRF shows larger than that by sliding mesh, possessing only about 12.3% error between two methods. The two calculation values of churning moment are basically consistent, but the calculation cost of MRF is lower.