A mask assembly and an apparatus and method for manufacturing a display apparatus are provided. A mask assembly includes a mask frame and a mask on the mask frame and having at least one opening. The mask includes a mask body portion having the at least one opening, and a protruding portion arranged to surround the at least one opening and including an inner surface defining the at least one opening, the protruding portion protruding from the mask body portion and configured to protrude toward a display substrate and contact the display substrate. A deposition material is configured to pass through the at least one opening to be deposited in an entire display area of a display panel including a plurality of pixels.