A deposition mask includes a deposition pattern through which a deposition material passes and a distal end extended in a length direction of the deposition mask from the deposition pattern. The distal end includes a dummy pattern between a clamping groove and the deposition pattern in the length direction. The clamping groove and the dummy pattern are provided in plural along a second direction crossing the length direction. In the length direction of the deposition mask, the number of clamping grooves and dummy patterns correspond to each other, the clamping grooves respectively overlap a corresponding dummy pattern, a distal end area at which clamping grooves overlap the corresponding dummy pattern defines a second area of the distal end, and a distal end area at which the clamping grooves do not overlap the corresponding dummy pattern defines a first area of the distal end to which a clamp is applied.