Abstract:The internal dynamic friction torque of the highspeed spindle roller bearings is one of the key technical parameters determining the highspeed performance of the bearing,such as friction and wear,heat,temperature rise and life.Based on the principle of balance torque method,a dynamic friction torque testing machine for high speed spindle roller bearings was developed according to the specific structural characteristics and operating conditions of roller bearings.The tester can measure dynamic friction torque of the bearings with different clearance,different speed,different load conditions,can also monitor the dynamic friction torque in all stages of the bearing life cycle.The test results of the test machine are in good agreement with the results of the model in the literature,validating thta it is feasible to test the dynamic friction torque of the high speed spindle roller bearing based on the principle of balance moment method.