An illumination unit includes a light guide having an incidence surface, a frame which is spaced apart from the incidence surface of the light guide, an accommodation section which is formed between the incidence surface of the light guide and the frame, and a light source unit including light-emitting diodes, a film substrate on which the light-emitting diodes are amounted, a heat radiation member having a support portion which supports the film substrate and a reflection portion which extends from the support portion, and an adhesive tape which adheres the film substrate to the support portion and has heat radiation properties, the light source unit being accommodated in the accommodation section.