We present a hybrid sunlight and light-emitting diode (LED) lighting system design for indoor illumination. Sunlight is collected by a set of sunlight concentrator and then split into visible and non-visible rays by a beam splitter. The visible rays pass through the light guide into a light box. The sunlight and LED light are combined and made uniform by the light box, if the sunlight is not bright enough, some of these 140 LEDs can be turned on to maintain indoor illuminance above the standard level. When nighttime comes, all the LEDs can be turned on to illuminate the indoor space. The lighting system can let the lighting environment green and comfortable. Our simulation of the illumination system shows that the efficiency of the sunlight and LED hybrid lighting combination is better than that of LED and traditional lighting systems.