Starting from the space-translated version of Schr?dinger equation of H-atoms in the laser fields with circular polarization, the features of the dressed coulomb potential are analyzed, a small expansion parameter is found and a perturbation-iteration method is presented. Then the zero to second order approximation equations of Floquet-Schr?dinger equation are derived It is shown that the above-mentioned expansion in the small parameter makes the iteration method to give a correct result. Furthermore, the advantages of the approach are qualitatively displayed by a brief comparison of the results given in this paper with the previous results.