A bacterial strain, designated Jyi-05(T), was isolated from a flooded rice field and characterized using a polyphasic taxonomic approach. Cells of strain Jyi-05(T) were Gram-stain-negative, strictly aerobic, bright-yellow-pigmented rods that were motile by gliding. Growth occurred at 10-30 �XC (optimum 30 �XC), at pH 6.5-7.5 (optimum pH 7.0) and with 0-2% (w/v) NaCl (optimum 1%, w/v, NaCl). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain Jyi-05(T) belonged to the genus Flavobacterium and was most closely related to Flavobacterium flevense DSM 1076(T) with sequence similarity of 97.6%. Strain Jyi-05(T) contained iso-C(15:0) (16.6%), anteiso-C(15:0) (10.8%), summed feature 3 (C(16:1)�s7c and/or C(16:1)�s6c; 10.3%), iso-C((17:0) 3-OH (9.2%), C(16:0) (7.3%) and iso-C(15:0) 3-OH (7.2%) as the predominant fatty acids. The major isoprenoid quinone was MK-6. The polar lipid profile consisted of phosphatidylethanolamine and several uncharacterized aminophospholipids and phospholipids. The major polyamine was homospermidine. The genomic DNA G+C content of strain Jyi-05(T) was 34.2 mol%. The DNA-DNA relatedness of strain Jyi-05(T) with respect to recognized species of the genus Flavobacterium was less than 70%. On the basis of the phylogenetic inference and phenotypic data, strain Jyi-05(T) should be classified as a novel species, for which the name Flavobacterium oryzae sp. nov. is proposed. The type strain is Jyi-05(T) (= BCRC 80522(T) =LMG 27292(T) =KCTC 32240(T)). Emended descriptions of Flavobacterium flevense, Flavobacterium yonginense and Flavobacterium myungsuense are also presented.