The utility model provides an illumination device. The illumination device (10) is provided with a common body (11), a light source unit (12) and a light control unit (13). The common body (11) is opened in the front part and the rear part, a front side common installation part (24) is arranged on the front side, and a rear side common installation part (22) is arranged on the rear side. The light source unit (12) is provided with a plurality of light source parts (35) and a radiator (36) provided with the light source parts (35), light-emitting elements (38) are used in the light source parts (35), and the light source unit (12) is installed on the rear side common installation part (22) of the common body (11). The light control unit (13) is provided with a plurality of reflectors (49) which are opposite to the light source parts (35) respectively to control light distribution, and the light control unit (13) is installed on the front side common installation part (24) of the common body (11). According to the illumination device, the common body can be used as a common structure, and the illumination device can correspond to different kinds of light output or light distribution.