In a liquid crystal display device, a reflecting surface is attached to a portion, which overlaps with a periphery portion of a light guiding plate where the light incident section is position in a surface on the light guiding plate side in the dispersing sheet which is positioned farthest to the light guiding plate side among a plurality of optical sheets which are positioned between the light guiding plate and a liquid crystal panel. As a result, light which is emitted from the periphery portion of the light guiding plate is returned into the light guiding plate by being reflected by the reflecting surface, and after this, is emitted as illumination light from a light emitting surface while progressing within the light guiding plate.