Abstract: In order to study the effect of ultrasonic rolling processing on the rolling contact fatigue resistance of GCr15SiMn bearing ring surface, the rolling contact fatigue test of GCr15SiMn bearing rings before and after ultrasonic rolling processing were carried out. The surface morphology and microstructure of two fatigue failure bearing rings were observed and compared by three-dimensional microscope and scanning electron microscope（SEM）. The results show that the contact fatigue life of the bearing ring after ultrasonic rolling is improved, and it is about 3 times of the average fatigue life of the bearing ring without ultrasonic rolling. The bearing ring processed by ultrasonic rolling can resist the substantial increase of surface hardness caused by ball rolling. Compared with the fatigue parts without ultrasonic rolling bearing ring, the average surface roughness and maximum surface roughness of the fatigue failure ultrasonic rolling bearing ring are significantly reduced, the ability to resist the surface plastic deformation is enhanced, the number of surface pitting is reduced, and the surface fatigue micro cracks are changed to parallel arc arrangement, which resists the initiation of fatigue micro cracks at the grinding fine grains.