A display device includes a foldable case unit and a flexible display panel. The case unit includes an elongated connecting plate, and a lower case and an upper case coupled to the connecting plate via hinge parts, respectively. The upper case has a variable dimension in a y direction. In the opened case unit, the lower case, the connecting plate, and the upper case are aligned flush with one another in the y direction. In the folded case unit, the dimension of the upper case in the y direction is larger than the dimension in the opened case unit, and the display panel is accommodated in a space surrounded with the lower case, the connecting plate, and the upper case.