ILLUMINATION DEVICE

An illumination device includes a plate-shaped light-transmitting member having a light-transmitting region, a fixture having a box shape with one open surface, the fixture attached to the light-transmitting member such that the open surface faces the light-transmitting member, and a light emitting module inserted into the fixture. The fixture includes an insertion opening formed on a surface perpendicular to the open surface, the light emitting module slidingly inserted into the insertion opening along the light-transmitting member. The light emitting module includes a planar light emitter having a light emission surface and a holder configured to hold the planar light emitter and configured to engage with the fixture such that the light emission surface overlaps with the light-transmitting region. The holder protrudes in an insertion direction of the light emitting module beyond a contour of the planar light emitter.