A Gram-negative, rod-shaped, non-spore-forming bacterium (designated strain Kw05(T)) was isolated from granules used in the wastewater treatment plant of a beer-brewing factory in Kwang-Ju, Republic of Korea. On the basis of 16S rRNA gene sequence similarity, strain Kw05(T) was shown to belong to the family Flavobacteriaceae, and was most closely related to Flavobacterium limicola (96.6 %), Flavobacterium hibernum (96.3 %), Flavobacterium hydatis (96.1 %) and Flavobacterium xinjiangense (96.1 %). The G+C content of the genomic DNA of strain Kw05(T) was 36.2 mol%, within the range of 32-37 mol% for the genus Flavobacterium. Chemotaxonomic data (major menaquinone MK-6; major fatty acids iso-C(15 : 0), iso-C(17 : 0) 3-OH, iso-C(15 : 0) 3-OH and iso-C(17 : 1)omega9c) supported the classification of strain Kw05(T) within the genus Flavobacterium. Kw05(T) therefore represents a novel species, for which the name Flavobacterium granuli sp. nov. is proposed. The type strain is Kw05(T) (=KCTC 12201(T)=IAM 15099(T)).