A deposition mask in which a resin film can be completely removed in opening portions, a method of manufacturing the deposition mask, and a mask member for the deposition mask are provided. A light irradiation source for laser light is disposed on one side of a resin film (11) and emits the laser light for forming a pattern of opening portions. A reflective film (30) is provided on another side of the resin film (11) and reflects light having a wavelength of the laser light emitted from the light irradiation source for the laser light. The laser light reflected by the reflective film (30) is used to form the patterns of the opening portion (11a) in the resin film (11).