To improve the dynamic load resistance capability of the aerostatic bearing,the displacement impedance performance of the air film-floating facility system was studied,and the influence mechanism of bearing parameters on displacement impedance was discussed.The numerical simulation and dynamic mesh method were adopted to discuss the air film stiffness and damping characteristics.The displacement impedance performance of the air film-floating facility system was investigated,and the influence characteristics of excitation-frequency,orifice diameter,air film thickness and air supply pressure on the displacement impedance were discussed.The optimization was conducted under a series of excitation frequencies to achieve the bearing parameters with the maximum displacement impedance,and the mechanical performance was further discussed based on the optimization.The results indicate that the displacement impedance increases with increase of the excitation frequency,and other parameters have non-monotonic influences on the displacement impedance.The higher displacement impedance can be achieved with a small air film thickness,however,only by increasing or decreasing the air supply pressure cannot enhance the displacement impedance,that is,the dynamic load resistance capability of the air film cannot be improved by only adjusting the supply pressure.Because the displacement impedance directly reflects the dynamic load resistance capability of the air film,the improvement of the displacement impedance through design optimization can certainly enhance the dynamic load resistance capability of the air film,improve the dynamic performance of the aerostatic bearing.The optimization modelling procedure can provide a reference for the aerostatic bearing design to enhance the dynamic performances.