Abstract: In order to the characteristics that the small loading capacity and low stiffness of traditional aerostatic bearing, a groove with rectangle section is designed. The axial section of radial groove is rectangle and the radial section of radial groove is fan-shaped. CFD model of aerostatic bearing with radial groove is established. The effect of the number of grooves, depth, angle of radial groove and supply pressure on the loading capacity and stiffness of aerostatic bearing are studied. The result showed that the loading capacity of aerostatic bearing increases with the increase of the number of grooves, depth, angle of radial groove and supply pressure, decreases with the increase of gas film thickness. With the increase of the angle of the radial groove, the thickness of the gas film corresponding to the peak value of the stiffness have no significant change. With the increase of the number of the radial groove, the thickness of the gas film corresponding to the peak value of the stiffness have a slight increase. With the increase of the supply pressure, the peak value of the stiffness also increase.