An apparatus for manufacturing a display device and a method of manufacturing the display device are provided. The apparatus for manufacturing the display device includes: a mounting unit, on which a display substrate may be arranged; an inspection unit movably arranged on the mounting unit and configured to inspect whether or not an organic encapsulation layer of the display substrate is defective; and a repair unit movably arranged on the mounting unit and configured to supply an organic material to a defective portion of the organic encapsulation layer, or to remove at least a portion of the defective portion of the organic encapsulation layer.