Finite element method was used to solve the Reynolds equation of the gas flow field in aerostatic spindle and the steady performances were calculated such as load capacity,stiffness and height angle.Moreover,the effects of average airfilm thickness,eccentricity,orifice diameter factor (ratio of adjacent throttle diameters) and orifice distribution factor (ratio of adjacent throttle intervals) on the steady performances were studied.The results demonstrate that load capacity and stiffness decrease while height angle increases with the growth of orifice diameter factor;load capacity and stiffness increase while height angle decreases with the increase of orifice distribution factor.Further,load capacity and stiffness decrease and height angle decreases firstly then increases with the increase of average airfilm thickness if orifice diameter factor and orifice distribution factor are constant.The larger the eccentricity is,the higher the load capacity is and the smaller the stiffness is.Height angle increases with the growth of rotational speed increases.It is helpful for increasing load capacity and stiffness and decreasing height angle if the spindle with small orifice diameter factor and large orifice distribution factor.It has large load capacity and stiffness if the spindle with small average airfilm thickness.Larger eccentricity increases spindle load capacity and reduces stiffness.