A mask frame assembly including a frame including a first opening, a first mask including second openings that each has an area smaller than the first opening and a first surface having portions of the first surface connected to the frame. The mask frame assembly includes second masks disposed on a second surface of the first mask extending across the first opening in a first direction and arranged in a second direction that is substantially perpendicular. The second masks include pattern parts having a shape corresponding to the second openings. The pattern parts each include pattern holes configured to allow a deposition material to pass through. The second masks include a rib part disposed between the pattern parts. The rib part includes dummy holes each having an area greater than each of the pattern holes. The first mask is configured to block the deposition material passing through the dummy holes.