A Gram-staining-negative, moderately halophilic and strictly aerobic bacterium, designated strain KJ4T, was isolated from marine sediment at Gangjin in South Korea. Cells were catalase- and oxidase-positive long rods with gliding motility. Growth of strain KJ4T was observed at 4-37 °C (optimum, 15-25 °C), at pH 6.0-9.0 (optimum, pH 7.0-8.5) and in the presence of 1.0-7.0% (w/v) NaCl (optimum, 2.0-5.0%). Menaquinone 6 (MK-6) was the only isoprenoid quinone detected and iso-C15:0, iso-C17:0 3-OH, iso-C15:1 G and summed feature 3 (comprising C16:1ω7c and/or C16:1ω6c) were the major cellular fatty acids. The polar lipids of strain KJ4T consisted of phosphatidylethanolamine, an unidentified aminophospholipid and five unidentified lipids. The G+C content of the genomic DNA was 38.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain KJ4T formed a distinct phylogenetic lineage within the genus Maribacter. Strain KJ4T was most closely related to Maribacter orientalis KMM 3947T with 97.4% 16S rRNA gene sequence similarity. On the basis of phenotypic, chemotaxonomic and molecular features, strain KJ4T clearly represents a novel species of the genus Maribacter, for which the name Maribacter lutimaris sp. nov. is proposed. The type strain is KJ4T (=KACC 16438T=JCM 31154T).