The reflection and transmission of coaxial waveguide partially filled with chiral media were solved by a method which combined the multimode network theory with a rigorous mode matching procedure. Equivalent radial transmission lines in the transveral cross section and multimode transmission lines in the longitudinal direction were introduced. The symmetrical property of the structure in the longitudinal direction was considered so that the whole analysis could be simplified. Effect of chirality and permittivity on the reflection and transmission was discussed.