The invention discloses a liquid crystal display device. The liquid crystal display device comprises a back plate, a reflective sheet, a lamp bar, a light guide plate, a liquid crystal display screen, a middle frame and a connecting piece. The back plate comprises a bottom plate and side walls extending upwards from the four sides of the bottom plate, and a containing cavity is defined by the side walls and the bottom plate. The reflective sheet, the lamp bar and the light guide plate are all located in the containing cavity, the reflective sheet is located between the light guide plate and the bottom plate, and the lamp bar is fixedly connected with the bottom plate and located on one side of the light guide plate. The connecting piece is fixedly connected with the middle frame, the liquid crystal display screen and the back plate, so that the middle frame, the liquid crystal display screen and the back plate are fixed. The light guide plate is connected to the back plate in a pressed mode through the middle frame. According to the liquid crystal display device, production cost is reduced, and frameless design is achieved.