In a method of manufacturing an illumination device, a color tone of each of a plurality of light emitting devices having different color tones is detected. In which region among a first region, a second region, a third region, a fourth region, a fifth region, and a sixth region on a chromaticity diagram the color tone of each of the plurality of light emitting devices is determined based on the detected color tone. The chromaticity diagram has a first color tone area and a second color tone area in which the first color tone area is provided. The second color tone area is divided into the first region through the sixth region. The plurality of light emitting devices are classified into the first region through the sixth region based on the determined color tone.