A backlight unit, a display device including the backlight unit, and a method of manufacturing the backlight unit are provided. The backlight unit may include a light guide plate configured to provide light for a two-dimensional (2D) image and light for a three-dimensional (3D) image to a display panel, and the light guide plate may include a first output pattern formed on an upper surface of the light guide plate and configured to output the first light provided from the first light source to a display panel and a second output pattern formed on a lower surface of the light guide plate and configured to output the second light provided from the second light source to the display panel.