The supercritical carbon dioxide power cycle system has a very positive effect on the realization of energy saving and emission reduction goals. In this paper， a calculation model is proposed for a foil gas dynamic pressure bearing structure. By fitting the non-ideal state gas supercritical carbon dioxide， the relationship between density and pressure is established. Based on the heat transfer model and the gas lubrication energy equation， the temperature rise of the bearing gas film is analyzed. The Reynolds equa? tion of the lubricating gas is corrected in combination with the turbulent effect in the actual operation process， coupled with the me? chanical analysis model， Reynolds equation and energy equations， the static characteristics of foil gas dynamic pressure bearings are analyzed， and compared with air as a medium to analyze the influence of different system parameters and turbulence parameters on the bearing characteristics. The results show that compared with air， the foil gas dynamic pressure bearing using supercritical carbon dioxide as the lubricating gas has a higher bearing capacity， and within a certain range， the bearing capacity can increase with the increase of bearing diameter and width， eccentricity， the rotational speed and the reduction of the bearing clearance. For the turbulent influencing factors， within a certain range， the bearing capacity can increase with the increase of the local Reynolds number and turbulence coefficient， aerodynamic viscosity， density for ambient gas and the decrease of ambient temperature.