At present, a variety of machinery and equipment, instruments and other markets for micro-bearing performance quality requirements in all aspects of more and more stringent, and bearing working environment is more and more diverse. In order to select the most suitable micro-bearing son son sitin son s/he from a wide range of size strains, it is necessary to analyze and study from multiple angles. When we choose bearings, we should generally consider the installation, arrangement and removal of bearings as shaft systems, the size of the bearings, the space allowed and the marketability of the bearings, etc., first of all, the bearing structure is initially confirmed. Second, it is decided to select the dimensions of the bearings while comparing the mechanical design life of the equipment using bearings and the durability limits of various micro bearings. In addition to taking into account the fatigue life of bearings, we should also take into account the grease life and wear, noise and other factors related to the aging of grease when selecting bearings. Depending on the different uses of bearings, bearing clearance, precision, cage structure, grease should also be made corresponding requirements, if necessary, bearings can be specially designed. Select bearings do not have a specific order and rules, should be based on the actual situation to consider the required bearing conditions, performance and other related requirements.