Since the thickness of the air film in the aerostatic spindle is at the micron level,and the imbalance in the spindle will affect the change of the air film thickness in the bearing,it is necessary to consider all the micro-scale influencing factors comprehensively,and to fully consider all the factors affecting the spindle imbalance in order to truly reflect the flow state of the air film in the spindle and simulate the static performance of the bearing. The traditional Reynolds equation was modified by consider the microscale influencing factors to obtain the real situation of gas flow in the bearing.The effects of three microscale influencing factors,the viscosity, flow factor,speed slip,rotor eccentricity and manufacturing error on the static performance of the bearing were studied.Through experimental verification,the real prediction and analysis of the static characteristics of the aerostatic bearing were realized.The results show that among the three microscale influencing factors,the velocity slip has the greatest influence on the pressure distribution of the bearing.When three microscale influencing factors are considered at the same time,it can better reflect the real state of bearing film flow.When rotor eccentricity is coupled with manufacturing error,with the increase of rotor eccentricity,the difference between the gas film pressure distribution and the gas film stiffness near each orifice in the bearing becomes larger and larger,which will seriously affect the gas film stiffness of the bearing.