To study the effects of hydrodynamic and hydrostatic coupling effect on pressure distribution and load capacity of hydrostatic gas bearing,the flow field characteristic,coupling effect of hybrid gas bearing,bearing capacity,attitude angle were analyzed by Computational Fluid Dynamics (CFD) under different rotating speed and eccentricity ratio,by taking the highspeed hydrostatic gas bearing as research objective.The results show that the change of the gas viscous force,differential pressure flow and gas compressibility caused by rotating speed and eccentricity ratio influences the strength of hydrodynamic and hydrostatic coupling effect,causes the asymmetric distribution of circumferential pressure of flow fields,and the change of force and attitude angles.At the same eccentricity rate,the bearing capacity is increased with the increasing of the rotating speed,and the attitude angle is first increased and then decreased.At the same rotating speed,when the rotor is kept in a low speed range,the attitude angle is increased with the increasing of the eccentricity,while it is opposite at high speed.