To study the bearing steel balls combination ratio of different diameter for the surface hardness of bearing ring in reinforced grinding processing. The process of steel balls colliding the bearing ring surface was analyzed through theoretical and experimental study, and the changes in surface morphology were observed by using a scanning electron microscope (SEM). Its surface hardness was measured by Rockwell hardness tester and its surface roughness was measured by confocal laser scanning microscope in before and after processing. The results show that after the diameter of 2 mm and 3 mm balls combination ratio reinforcing the ring under the parameters of the experimental conditions，its valueadded of the surface hardness is the largest. The results of reinforced grinding are better，it effectively improves the surface hardness, and ensure the reinforced grinding quality.