A moderately halophilic, aerobic, Gram-negative bacterium was isolated from a tidal flat area of Dae-Chun, Chung-Nam, Korea. The strain, designated mano11(T), comprised rod-shaped cells that were motile by means of polar flagella. It grew with 3-12 % NaCl and at 4-37 degrees C and pH 5.3-9.3. The predominant menaquinone present in this strain was Q-8 [corrected] and diaminopimelic acid was not found in the cell-wall peptidoglycan. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain mano11(T) belongs to the genus Marinobacterium. Strain mano11(T) exhibited 92.8-98.3 % 16S rRNA gene sequence similarity when compared with the type strains of three other species of the genus Marinobacterium. DNA-DNA hybridization between strain mano11(T) and Marinobacterium georgiense DSM 11526(T), its closest relative in terms of 16S rRNA gene sequence similarity, was 13 %. On the basis of the phenotypic, genetic and phylogenetic data, strain mano11(T) represents a novel species of the genus Marinobacterium, for which the name Marinobacterium halophilum sp. nov. is proposed. The type strain is mano11(T) (=KCTC 12240(T)=DSM 17586(T)).