To discuss the impact of bearing parameters, including the restrictor size, air film thickness and air supply pressure, on mechanical performance of the orifice restricted aerostatic bearing. Firstly, taking the orifice restricted hydrostatic thrust bearing with cylindrical chamber for an example, carried out a numerical simulation and analyzed in the bearing clearance flow field, in which the orifice size, air chamber size, air supply pressure and air film thickness were taken as the design variables, established an orthogonal array by utilizing the basic principle of orthogonal experimental design, and then took samples through numerical calculation of the bearing clearance flow field to obtain load carrying capacity and stiffness of the bearing; secondly, built an analysis mathematical model for load capacity and stiffness, in which the functions of each parameter and the impact of flow field structure on the mechanical performance were taken into consideration, within the range of design variables based on the radial basis functions model, and the obtained model was proved with sufficient precision through fitting verification; finally, analyzed the impact of orifice size and air chamber size on load capacity and stiffness of the bearing, which provided a reference for engineering design.