A liquid crystal display device in an example includes a light guide plate that includes a light entering surface facing a light source; a reflecting plate below the light guide plate; an optical sheet on the light guide plate; a liquid crystal panel on the optical sheet; and a pattern adhesive layer that attaches at least one of the reflecting plate and the optical sheet to the light guide plate, wherein the pattern adhesive layer includes honeycomb shaped unit patterns that each include two first separation walls facing each other in a first direction perpendicular to the light entering surface, and second separation walls other than the first separation walls and each have an air cell defined therein, and wherein the unit patterns are arranged in the first direction and in a second direction perpendicular to the first direction.