Abstract: According to Ressner's plate theory,the basic differential equations of the nonlinear bending of circular medium pletes,under uniform pressure combined with concentrated load at the center,including the effect of transverse shear deformation,are derived.A load distribution function is introduced as to make the compound loads varying with a single load parameter. Average angular deflection is used as the single displacement perturbation parameter, by means of the perturbation method.A more high precise solution was obtained.