A display device is disclosed. The display device includes: a flexible display panel; a roller extending in a longitudinal direction, wherein the flexible display panel is wound around or unwound from the roller; a first end of the roller rotatably coupled to a first frame; a second frame rotatably coupled to a second end of the roller and disposed opposite to the first frame with respect to the roller; a door disposed adjacent to an end of the flexible display panel unwound from the roller and coupled to the first frame and the second frame; and a side brake positioned between the door and the roller and the side brake is adjacent to the first frame when the door is closed, wherein the side brake restricts rotation of the roller.