An analysis of electromagnetic wave propagation in multilayer mediums containing anisotropic material and a closed form representation of the electromagnetic field over the anisotropic region were presented.This structure can be used as a quasi optical Faraday rotator and as either an isolator or circulator when combined with other guasi optical components.It also can be used as a radiation aperture to realize the beam scanning or change of polarization by means of changing the direction and strength of the biased magnetic field.The calculated and experimental results of Faraday rotation were given.