Abstract-In this paper a novel approach based on Asymptotic Iteration Method (AIM) is presented to solve analytically the light propagation through one-dimensional inhomogeneous slab waveguide. Practically implemented optical slab waveguides based on traditional techniques are usually inhomogeneous and numerical methods are used to obtain guided wave characteristics. In this work, we develop analytical method for modal analysis includes Eigen modes (electric and magnetic fields distribution) and Eigen values (guided wave vector) using AIM. The developed method is applied to some especial examples.