Based on the nonperturbative quantum electrodynamics, we study the high-order above-threshold ionization (ATI) induced by rescattering process. By using a form al scattering theoretical approach, an analytic form of the high-order ATI spect rum is obtained. We discuss the interference effect of different ATI channels on the high-order ATI. The high-order ATI spectra due to the rescattering of electrons from different incident angles are also given.