Using the transfer matrix method, the dispersion curve and reflection spectrum of the metal-cladded uniaxial crystal waveguide structure are obtained. The waveguide modes of metal-cladded anisotropic planar waveguide can be excited by free space light, and the optical axis orientation of the uniaxial crystal modulates waveguide modes of the structure, makes Ey, Ez coupled into a hybrid waveguide mode (HGM) in the waveguide layer. By adjusting the coupling metal film thickness, polarization of the reflected light from the waveguide can be manipulated to realize TE-polarized incident light converting into TM-polarized output light or linearly-polarized incident light into circularly-polarized output light.