Abstract: Hydrostatic rotary table has been widely used in ultra-precision machine tools because of its excellent performance of high stiffness and high precision, which can be improved by selecting parameters of orifice diameter and bearing clearance. In order to further study the influence of the two parameters, an orifice compensated conical hydrostatic rotary table with orifice diameter and bearing clearance can be changed was designed. The stiffness of the rotary table was calculated by using fluid simulation method and validation experiments were then carried out. Firstly, the structure of conical hydrostatic rotary table was introduced, and the performance of it was theoretically calculated and analyzed. Then, the influence of orifice diameter and bearing clearance on the stiffness of hydrostatic rotary table was simulated and summarized in Fluent software. Finally, the rotary table was produced, and its axial and radial stiffness were measured, which were in good agreement with the simulation results, the reliability of the simulation model was proved. It is of great significance to the design and stiffness improvement of hydrostatic rotary table.