The illumination system used in liquid-crystal projection television requires high-efficiency and high-uniformity. The illumination system consisting of an ellipsoidal reflector and a scrambler, an illumination ens system is designed to satisfy those conditions. Analysis of the illumination system begins with the calculation on the path of ray reflected by ellipsoidal reflector from the light source. Next, the intensity distribution on the scrambler entrance window is obtained through the computer simulation and efficiency is cacluated. And then, he intensity distribution on the scrambler exit window is evaluated sing total internal reflection. Finally, the illumination lens system s constructed regarding exit window as an object and liquid crystal display panel as an image. It is found that the maximum-efficiency on the scrambler entrance window is about 57% and the intensity distribution on he scrambler exit window is uniform.