According to an arrangement, an additive manufacturing apparatus (1) includes a first irradiation unit (42), and a first emission device (41). The first irradiation unit (42) is configured to irradiate a material (3) with first light (L1) to melt or sinter the material (3). The first emission device (41) includes a first light source (41a) configured to emit the first light (L1), is configured to cause the first light (L1) emitted from the first light source (41a) to enter the first irradiation unit (42), and is capable of changing a wavelength of the first light (L1) entering the first irradiation unit (42).