A ctenostomatous bryozoan, Bantariella bocki is reported from Jejudo Island of South Korea. This is the first report from Korean waters. Each zooid is produced from each kenozooid which arranged in two and originated opposite each other at intervals of about 0.64 mm along the stolon. B. bocki collected from black corals is considered to be a invasive species introduced from Bonin Islands located in the subtropical waters. The redescription, some distributional remarks and illustrations of B. bocki are provided.