As the very small vibration of an aerostatic bearing limits its applications in ultra-precision machining, this paper analyzes experimentally the dynamical characteristics of the aerostatic bearing and proposes a structure design with an equalizing groove to solve the problem mentioned above. To realize the mechanical characteristics of aerostatic bearings, the analytical model was set up by using the finite element analysis software FLUENT and the performance parameters of the aerostatic bearing were obtained. The mechanism for the occurrence of small vibration was analyzed and the methods to add an equalizing groove on the surface of the aerostatic bearing to reduce the small vibration were proposed. The experiments were performed to verify the proposed method and the results show that the experiment results are good consistent with the analysis results. It indicates that the small vibration can be successfully suppressed by 80% with the proposed equalizing groove, which improves the stability and operation accuracy of the aerostatic bearing and is a useful exploring for suppressing the small vibration of aerostatic bearings and improving the accuracy of whole machine tool.