Pleurogrammus monopterygius was first collected from Daejin-ri, Goseong-gun, Gangwon-do, Korea on April 1999. This species is distinguished from its related species by having four to five broad blackish bands on the side of its body and different patterns of lateral lines. We gave P. monopterygius the new Korean name, "Dan-Gi-Im-Yon-Soo-Eo" and described the species in detail based on the study of specimens.