Two Gram-negative, non-motile, non-spore-forming, rod-shaped strains, SW-2T and SW-26, were isolated from sea water of the East Sea in Korea. These organisms grew optimally at 37 degrees C and in the presence of 2-3 % (w/v) NaCl. They did not grow without NaCl or in the presence of >9 % (w/v) NaCl. Strains SW-2T and SW-26 were characterized chemotaxonomically as having MK-7 as the predominant isoprenoid quinone and iso-C(15 : 0) as the major fatty acid. The DNA G + C content of strains SW-2T and SW-26 was 43 mol%. A neighbour-joining tree based on 16S rRNA gene sequences showed that strains SW-2T and SW-26 fell within the Cytophaga-Flavobacterium-Bacteroides group and formed a coherent cluster with Hongiella species. Strains SW-2T and SW-26 showed a 16S rRNA gene sequence similarity value of 99.9 % and a mean DNA-DNA relatedness level of 87 % to each other. Levels of 16S rRNA gene sequence similarity between strains SW-2T and SW-26 and the type strains of two Hongiella species ranged from 94.2 to 96.6 %. On the basis of phenotypic and chemotaxonomic properties and phylogenetic distinctiveness, strains SW-2T and SW-26 should be placed in the genus Hongiella as members of a novel species, for which the name Hongiella marincola sp. nov. is proposed. The type strain is SW-2T (= KCTC 12180T = DSM 16067T).