Three bacterial strains were isolated from sea-water samples taken from Amursky Bay of the Gulf of Peter the Great, East Sea. The isolates, designated KMM 3670, KMM 3673(T) and KMM 3928, were Gram-positive, non-motile, aerobic, non-spore-forming, irregular, rod-shaped actinobacteria. They grew well at mesophilic temperatures and neutral pH and tolerated up to 10 % NaCl, although salt was not essential for growth. The three strains shared all morphological properties and most physiological characteristics tested. Based on subsequent chemotaxonomic and phylogenetic analyses, it was evident that the strains represented a distinctive taxon in the family Microbacteriaceae. The strains contained a major amount of menaquinone with 11 isoprene units; lysine and ornithine were the major cell-wall diamino acids. In 16S rDNA analysis, the three strains formed an independent phylogenetic lineage within the tree encompassed by members of the family Microbacteriaceae. It is notable that the tested strains form the first described taxon of Microbacteriaceae that inhabits a marine aquatic environment. The three strains evidently merit recognition as a single species of a novel genus in the family Microbacteriaceae, for which the name Salinibacterium amurskyense gen. nov., sp. nov. (type strain, KMM 3673(T)=KCTC 9931(T)) is proposed.