A vertically structured, aluminum nitride-based semiconductor deep ultraviolet light-emitting device is provided that exhibits a high light emission efficiency and an improved yield. The aluminum nitride-based semiconductor deep ultraviolet light-emitting device includes: a conductive support substrate; a porous metal film having a conductive macroporous structure with a pore rate of from 10% to 50% inclusive; and an aluminum nitride-based semiconductor layer structural body with a light-emitting layer, the conductive support substrate and the aluminum nitride-based semiconductor layer structural body being bonded with the porous metal film interposed therebetween for electrical connection, wherein the aluminum nitride-based semiconductor deep ultraviolet light-emitting device has an emission peak wavelength of from 220 nm to 300 nm inclusive.