Brachysomophis porphyreus is an eel in the family Ophichthidae (worm/snake eels). It was described by Coenraad Jacob Temminck and Hermann Schlegel in 1846. It is a marine, temperate water-dwelling eel which is known from the northwestern Pacific Ocean, including Taiwan, China, and Japan. It is known to dwell at a depth of 20 metres, and makes burrows in mud, nearly deep enough to cover itself completely. Males can reach a maximum total length of 130 centimetres.