To provide a back light unit that reduces an uneven brightness and has a spatially uniform brightness distribution. According to an aspect of the present invention, the back light unit comprises an LED and a light guide plate for guiding light from the LED to a liquid crystal panel side, wherein a recess is provided on the back surface side of the light guide plate, wherein a plurality of LEDs are housed in the recess, and wherein a light amount limiting member is provided at a position facing the recess on s light exit surface side of the light guide plate. The light amount limiting member is configured, for example, by applying an ink with a predetermined optical property to a transparent sheet.