Halla okudai Imajima, 1967 is an oenonid annelid species that inhabits the intertidal and shallow subtidal zones in China, Malaysia, Australia and Japan. This species is harvested and used as fishing bait in Japan and Malaysia; however, it has been regarded as Near Threatened in Japan based on the categories of the Japanese Red List. Here, we reconstructed the molecular phylogeny of Oenonidae based on 16S rRNA gene sequences. This study provides a new record of H. okudai on Fukue Island, in the Goto Islands, Japan. Keywords: Akamushi, annelid, mitochondrial DNA, muddy sand bottom, Nagasaki Prefecture, polychaete.