An illumination device includes a light converter that primary light enters and that is configured to convert at least part of the primary light into secondary light having a second wavelength that differs from a first wavelength of the primary light and to diffuse the secondary light, a first reflector configured to reflect at least part of the diffused secondary light toward the light converter, and a holder holding at least one of the first reflector and the light converter. The first reflector and the light converter are separated from each other so that the primary light transmitted through the first reflector enters the light converter.