Abstract: We obtianed the scattering state analytical solutions of the Schrödinger equation for the improved Manning-Rosen potential. The explicitly calculation formula of phase shift is derived and the normalized radial wave functions of scattering states on the"K/2π scale" are presented. The energy levels of the bound states are also obtained by studying analytical properties of scattering amplitude. All data calculated by the above approximate analytical formulae are compared with those obtained by the previous. Numerical results show the accuracy of our results.