Abstract: For the shortcomings of stage lamps, such as a small changing range of beam angle and a poor uniformity of illuminance, here we presented a single zoom lens system based on the structure of total reflection lens and the principles of zoom lens group. The system was consisted of a collimating lens and a mobile focusing plate. By using SolidWorks software, the mirror plate of collimating lens was filled with circular arrays of irregular pentagon fly's-eye lens, and a circular array with regular hexagon fly's-eye lens was built on both side of the focusing plate. After matched with the type of S2WP full color red-green-blue-white(RGBW) LED light source, the system was simulated by using LightTools and the actual illumination efficiency was detected. The results show that, these structures set above can solve the poor performance of uniformity and color mixing on the stage lamp effectively. What's more, the light utilization efficiency of the stage lamp zoom lens system we presented above can reach up to 87%, and the changing range of beam angle(1/2 light intensity angle) can be from 4° to 53° under the focusing distance extent from 0 mm to 15 mm.