||Polarizer is one of the essential optical element in LCDs. Conventional polarizers show limited thermal stability, low resistivity against solvents and large thickness. To overcome these defects, thin film polarizers are in demand. One possible approach is based on the highly ordered guest-host system, in which the anisotropic absorption of light achieved by aligning dichroic dye(guest) in the cooperative motion of the LC(host) molecules. New reactive LC monomers were designed and synthesized, which contains photo-polymerizable acrylate groups. To characterize the monomer 1H-NMR, DSC and POM were used. The monomer possess highly ordered smectic phase at relatively low temperature. We fabricated thin film polarizer in a sandwich cell. High dichroic ratio(DR) and order parameter(S) were determined by polarized UV/Vis spectroscopy, which is much higher than the nematic thin film polarizers.