In order to meet the development needs of ultraprecision manufacturing equipment and improve the bearing capability of aerostatic bearing,a composite aerostatic bearing with slit inlet and triangular pressure grooves was designed.The structure was modeled and simulated,the influence of different number,radiation angle,thickness and radius of the pressure grooves on the static performance of the aerostatic bearing structure was analyzed.The results show that the radius and numbers of the groove have a significant effect on the peak stiffness,and the change in the depth and angle of the pressure grooves can cause the stiffness peak to appear at different air film thicknesses;the volume of the pressure grooves increases,the bearing capacity and the loss of flow mass increase.