A deposition mask includes: a first mask having an opening formed therein; and a second mask superposed on the first mask and having a plurality of through-holes formed therein, the through-hole having a planar dimension smaller than a planar dimension of the opening; wherein: the deposition mask has a plurality of joints that join the second mask and the first mask to each other; the plurality of joints are arranged along an outer edge of the second mask; and a notch is formed at a position in the outer edge of the second mask, the position corresponding to a space between the adjacent two joints.