A Gram-positive, non-motile, coccoid-shaped, non-spore-forming halophilic bacterial strain, BY-5(T), was isolated from a marine solar saltern in Korea and its taxonomic position was investigated by using a polyphasic approach. The novel strain grew optimally at 37 degrees C and in the presence of 10 % (w/v) NaCl. Strain BY-5(T) had meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan, MK-7 as the predominant menaquinone and anteiso-C(15 : 0), iso-C(15 : 0), anteiso-C(17 : 0) and iso-C(17 : 0) as the major fatty acids. The DNA G+C content was 47.9 mol%. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain BY-5(T) formed a coherent cluster with Bacillus halophilus and Marinococcus albus. Strain BY-5(T) exhibited 16S rRNA gene sequence similarity values of 98.7 and 97.4 % to the type strains of B. halophilus and M. albus, respectively. Strain BY-5(T) was distinguished from B. halophilus and M. albus by several phenotypic properties and DNA-DNA relatedness data. On the basis of the combined chemotaxonomic and phylogenetic data, it is proposed that M. albus, B. halophilus and strain BY-5(T) should be placed in a new genus as three separate species. Marinococcus albus and Bacillus halophilus are reclassified in a new genus, Salimicrobium gen. nov., as Salimicrobium album comb. nov. and Salimicrobium halophilum comb. nov., respectively. The type species of the new genus is Salimicrobium album. Strain BY-5(T) (=KCTC 3989(T)=CIP 108918(T)) is placed in the genus Salimicrobium as a novel species Salimicrobium luteum sp. nov.