A deposition mask comprises a mask body comprising a plurality of through holes; and a deposition layer formed on external surfaces of the mask body. A method of manufacturing a deposition mask comprises: installing a deposition mask body in a chamber; forming a magnetic field between a plurality of magnet units within the chamber, wherein the deposition mask body is disposed between the magnet units; and applying voltages to first and second sputtering targets comprising a material to generate electric discharge such that particles of the material are sputtered from the first and second sputtering targets and deposited on the deposition mask body, thereby making a deposition mask with a layer of the material. The voltages having different magnitudes are applied to the first and second sputtering targets.