A deposition mask apparatus including a frame, a supporter including a plurality of supporting members fixed to the frame, and a deposition mask fixed to the frame is provided. The plurality of supporting members include at least a first supporting member that is closest to an intermediate position between a third portion and a fourth portion of the frame and a second supporting member that is located closer to the third portion of the frame than the first supporting member. The first supporting member in a state of warping downward from the frame with a first warping amount supports the deposition mask from below. The second supporting member in a state of warping downward from the frame with a second warping amount that is smaller than the first warping amount supports the deposition mask from below.