Abstract: A hydrostatic gas bearing having particular damping characteristics is provided. The hydrostatic gas bearing is of the orifice type having an air groove communicated with a gas injection port, wherein when a bearing clearance is denoted by h and a depth of the air groove by g, h is not larger than 5 &mgr;m and g/h is not smaller than 5. The material of the guide, slider and orifice constituting the bearing is alumina, silicon carbide, silicon nitride, Sialon, cordierite, or a composite ceramic including any one of them, as a main component.