Abstract: To investigate the influence of radial working clearance on the slip characteristics of cage-free angular contact ball bearings, firstly, based on quasi-static analysis of the bearing contact positions, the frictional angle and gyroscopic torque were introduced as the judgment conditions of the axial plane slippage, and the calculate calculation formula of critical radial working clearance of bearings was derived. Secondly, the finite element model of the cage-free bearing was established, and the dynamic running data of the bearing was obtained by simulation calculation. Finally, compared with the calculated results of the theoretical model, the method's effectiveness is verified. The results show that under the same rotational speed and load conditions, the slip rate decreases with the decrease of radial working clearance. However, when the unilateral radial working clearance decreases to −24 μm, the frictional angle of the axial plane is locked, and the gyroscopic speed of the ball in the axial plane is at a low level. and the slip rate of the bearing will increase if the radial working clearance continues to be reduced.