Aimed at the structural characteristics of foil hydrodynamic thrust gas bearing with hemispherical convex dots,a finite element model of the elastic foundation was established and solved by using ANSYS software.The influence of changing size of a single hemispherical convex dot on its stiffness was firstly analyzed by ignoring the deformation of top foil,and the model of the bearing was built and solved by finite difference method to obtain the film pressure.The deformations of top foil and the foil with hemispherical convex dots were obtained by applying the film pressure obtained by finite difference method.The results indicate that the structural stiffness of elastic foundation is increased by reducing the radius or the span of hemispherical convex dot or increasing the foil thickness.The top foil plays a major role in the deformation of the elastic foil element,and the amount of the deformation of the elastic foil element can meet the requirement of minimal film thickness of bearing lubricant layer.