A semiconductor light-emitting device includes a support structure, and a light-emitting structure. The support structure includes a support substrate, and a support substrate side bonding layer disposed on one surface of the support substrate. The light-emitting structure includes a light-emitting structure side bonding layer bonded to the support substrate side bonding layer, a reflection region disposed on the support substrate side bonding layer opposite the support substrate, and a semiconductor multilayer structure including a light-emitting layer disposed on the reflection region opposite the light-emitting structure side bonding layer for emitting a light with a predetermined wavelength, and a light-extraction surface disposed on the light-emitting layer opposite the reflection region for reflecting diffusely the light. The reflection region includes a transparent layer of a material with a lower refractive index than that of the semiconductor multilayer structure, and a reflection layer of a metallic material. The transparent layer has such a thickness that interference caused by multiple reflection of light inputted to the transparent layer can be suppressed.