A backlight unit and a liquid crystal display device having the backlight unit are discussed. According to an embodiment, the backlight unit includes a frame including an opening, a light guide plate attached to the frame and formed larger than the opening, an adhesive member formed between the light guide plate and the frame, a colored light source providing colored light to the light guide plate, and a fluorescent excitation sheet formed on the light guide plate to emit colored light incident through the light guide plate as white light, wherein the adhesive member is disposed around lateral sides of the light guide plate.