In order to improve the static characteristics of the aerostatic thrust bearings, the Fluent in CFD software based on finite volume method was used to simulate the three-dimensional modeling of the micro-orifice restrictor aerostatic thrust bearings. The effects of the orifice number n, non-dimensional orifice distribute radius M and the orifice diameter d on the static characteristics of the bearings were studied. According to the principle of maximum static stiffness, the following conclusions are obtained that when the orifice number n is about 180, non-dimensional orifice distribute radius M is about 0.7, orifice diameter d is 0.1 mm, the static characteristics of the micro-orifice restrictor aerostatic thrust bearings are optimum.