Disclosed is a heat radiator which is provided in a transmissive display unit in which a plurality of rows of light emitting arrays constituted by arranging a plurality of light emitting units including a plurality of LEDs mounted on a wiring substrate are arranged on the back surface side of a transmissive display panel, and illuminating light emitted from the LEDs is irradiated onto the display panel. In the heat radiator, a radiation plate (28) supporting LEDs (18) and a heat sink (37) constitute an overlap area (57) with a back panel (13) interposed therebetween and are integrated with each other through the back panel by a fixing member in the overlap area. The back panel, radiation plate, and heat sink are firmly mounted to each other, achieving effective heat radiation.