A deep-dwelling goby, Obliquogobius yamadai, was described as the first record from Korea based on three specimens (30.3~47.0 mm SL) collected from the southern sea off Jeju Island. The species is characterized by having I, 9 second dorsal fin rays, scaled lateral side of nape, smaller head with large eye, and asymmetrical caudal fin dorsoventrally as well as about nine yellowish bars on body side. A new Korean name, "Gip-eun-ba-da-no-ran-ddi-mang-dug", is proposed for the species.