A foldable display device in which a plurality of chassis are foldably coupled, comprising: a first chassis; a second chassis; a pivot coupling portion that couples the first chassis and the second chassis to allow an open state and a closed state, the first chassis and the second chassis being open to enter a planar state in the open state, the first chassis and the second chassis being closed to enter a state of being bent inward in the closed state; a flexible display arranged to cover one surface of the first chassis and one surface of the second chassis; and a support member arranged between the first chassis and the second chassis, the support member having a flat support surface that supports the display when the display is in the open state, wherein the display includes adhesive portions (7a, 7b) and a non-adhesive portion, the adhesive portions (7a, 7b) are adhered to the first chassis and the second chassis, and the non-adhesive portion is supported by the flat support surface of the support member when the display device is in the open state and is separated from the flat support surface of the support member between the first chassis and the second chassis when the display device is in the closed state; characterized in that the support member has a first curved surface and a second curved surface corresponding to portions of a circular arc around a pivot center of the pivot coupling portion when viewed in a direction in which a pivot axis of the pivot coupling portion extends, and the first chassis and the second chassis have a third curved surface and a fourth curved surface that complementarily support the first curved surface and the second curved surface, respectively. a first chassis; a second chassis; a pivot coupling portion that couples the first chassis and the second chassis to allow an open state and a closed state, the first chassis and the second chassis being open to enter a planar state in the open state, the first chassis and the second chassis being closed to enter a state of being bent inward in the closed state; a flexible display arranged to cover one surface of the first chassis and one surface of the second chassis; and a support member arranged between the first chassis and the second chassis, the support member having a flat support surface that supports the display when the display is in the open state, wherein the display includes adhesive portions (7a, 7b) and a non-adhesive portion, the adhesive portions (7a, 7b) are adhered to the first chassis and the second chassis, and the non-adhesive portion is supported by the flat support surface of the support member when the display device is in the open state and is separated from the flat support surface of the support member between the first chassis and the second chassis when the display device is in the closed state; characterized in that the support member has a first curved surface and a second curved surface corresponding to portions of a circular arc around a pivot center of the pivot coupling portion when viewed in a direction in which a pivot axis of the pivot coupling portion extends, and the first chassis and the second chassis have a third curved surface and a fourth curved surface that complementarily support the first curved surface and the second curved surface, respectively.