The dynamic friction torque of micro bearings is very small and has lots of influence factors,so it is difficult to measure accurately and chronically.According to the principle of torque balance,the test machine of the friction torque of micro bearings was developed by using the technology of highspeed spindle and precisionbalance measurement.The test machine is able to apply axial and radial load to micro bearings and simulate the actual conditions of micro bearings.It can truly reflect the dynamic friction torque of micro bearings during operation.The test proves that the test machine is simple,effective and has higher accuracy.And it can be used to measure the dynamic friction torque of micro bearings for a long time.Meanwhile it can be used to simulate and analyze the dynamic friction torque of the micro bearings under different working conditions and the whole life cycle.