An optical device manufacturing method including the steps of: forming a groove with a depth corresponding to a finish thickness of the heat sink in a heat sink material at a position corresponding to an associated one of the streets sectioning the plurality of optical devices; joining the optical device layer of the optical device wafer to the heat sink material via a joining metal layer; cutting and dividing the optical device wafer along the streets into individual optical devices; sticking a protection member to the rear surface of the substrate of the optical device wafer; and grinding the rear surface of the heat sink material to expose the grooves to the rear surface to thereby divide the heat sink material into heat sinks corresponding to associated individual optical devices.