Two Gram-stain-negative, obligately aerobic, non-motile, rod-shaped bacterial strains, designated SP3T and SP38, were isolated from a cold-water lake in the west of China. A polyphasic taxonomic study was performed for the strains. Alignment of 16S rRNA gene sequences indicated that strains SP3T and SP38 were associated with the genus Flavobacterium and were most closely related to Flavobacterium lacus NP180T (96.4 % sequence similarity), Flavobacterium ponti GSW-R14T (95.6 %) and Flavobacterium yanchengense hgT (95.3 %). The genomic DNA G+C contents of strains SP3T and SP38 were 34.9 and 34.6 mol%, respectively. The major fatty acids were iso-C15 : 0, iso-C15 : 1 G, summed feature 9 (iso-C17 : 1�s9c and/or 10-methyl C16 : 0), iso-C17 : 0 3-OH and iso-C15 : 0 3-OH. The unique respiratory quinone was menaquinone 6 (MK-6). The polar lipid profile consisted of phosphatidylethanolamine, one unidentified aminolipid and several unidentified polar lipids. Based on physiological, biochemical and phylogenetic data for these isolates, it was confirmed that strains SP3T and SP38 were affiliated to the genus Flavobacterium and represented a novel species, for which the name Flavobacterium orientale sp. nov. is proposed. The type strain is SP3T (=CGMCC 1.12506T=NBRC 109717T).