A Gram-positive-staining, rod-shaped, facultatively oligotrophic bacterial strain, designated MB18(T), was isolated from a water sample collected from the River Mahananda at Siliguri (26° 44' 23.20' N, 88° 25' 22.89' E), West-Bengal, India. On the basis of 16S rRNA gene sequence similarity, the closest relative of this strain was Brevibacterium epidermidis NCDO 2286(T) (96 % similarity). The DNA G+C content of strain MB18(T) was 64.6 mol%. Chemotaxonomic data [MK-8(H(2)) as the major menaquinone, galactose as the sole cell-wall sugar, meso-diaminopimelic acid as the diagnostic cell-wall diamino acid, phosphatidylglycerol and diphosphatidylglycerol as constituents of the polar lipids, anteiso-C(15 : 0), anteiso-C(17 : 0) and iso-C(15 : 0) as the major fatty acids] supported the affiliation of strain MB18(T) to the genus Brevibacterium. The results of DNA G+C content, 16S rRNA gene sequence analysis and biochemical and physiological analyses allowed genotypic and phenotypic differentiation of strain MB18(T) from its nearest neighbour B. epidermidis. The isolate therefore represents a novel species, for which the name Brevibacterium siliguriense sp. nov. is proposed; the type strain is MB18(T) ( = DSM 23676(T) = LMG 25772(T)).