An illumination device using a plurality of LED light sources each of which is driven by a single power supply is provided to attain simple operational response and voltage control.The illumination device includes a light source module, the module comprising: a substrate; a plurality of wiring lines provided on the substrate; and a plurality of LED devices implemented in the wiring lines; wherein the plurality of LED devices include a plurality of red LED devices, a plurality of green LED devices, and a plurality of blue LED devices; wherein the plurality of wiring lines include a wiring line having the plurality of red LED devices implemented in series, a wiring line having the plurality of green LED devices implemented in series, and a wiring line having the plurality of blue LED devices implemented in series; and wherein the plurality of wiring lines are connected in parallel and driven by a single power voltage.