Green and red fluorescence of dichroic dyes can be sensitized by adding blue fluorescent dyes in a nematic liquid crystal(LC). The excitation energy of a ultraviolet(UV)light transfers to an emitter through sensitizers and fluorescence intensity increases by 3greater than or similar to13 times. Relations between absorption and emission dichroic ratios of sensitizers and emitters have been measured and discussed. The voltage dependence of fluorescence intensity is also measured in the fluorescent guest host LC cell. The brightness and contrast ratio can be enhanced by adding the sensitizer of which dichroic ratio is higher than that of the emitter.