PURPOSE: A door device is provided to be made small and light and supply enough damping force, since a space for accepting hydraulic medium is maximized. CONSTITUTION: A door device comprises a first hinge unit(20), a second hinge unit(30), and a side cover(10). The first hinge unit is embedded on one side of the upper end of a door panel and rotates the door panel around an upper axis support piece fixed to a door frame(2). The second hinge unit is embedded on one side of the lower end of the door panel and rotates the door panel around a lower axis support piece fixed to a lower door frame(3). The buffer force is offered in open and close operation of the door panel and the sudden operation of the door panel is controlled. The side cover covers one rim of the door panel and supports the first and the second hinge units to hide the first and the second hinge units.
