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Two Gram-stain-negative, non-motile, rod-shaped bacterial strains were isolated from the surfaces of rice roots. They were designated as strains 1303 T and 1310. Their colonies were circular, entire, opaque, convex and yellow. They were chitinase- and catalase-positive, reduced nitrate and grew at 16-37 °C (optimum, 30 °C), pH 5.0-10.0 (optimum, pH 7.0) and 0-2.0% NaCl (optimum, 1.0 %). Based on the 16S rRNA gene sequence analysis, they were classified as members of the genus Chitinophaga . Results of phylogenetic and phylogenomic analyses indicated that they formed a cluster with Chitinophaga eiseniae YC6729 T , Chitinophaga qingshengii JN246 T , Chitinophaga varians 10-7 W-9003 T and Chitinophaga fulva G-6-1-13 T . When the genomic sequences of strains 1303 T and 1310 were compared with their close relatives, the average nucleotide identity and digital DNA-DNA hybridization values were below the cut-off levels. Phosphatidylethanolamine was the major polar lipid. MK-7 was the major respiratory quinone. iso-C 15 : 0 , C 16 : 1  ω 5c, iso-C 17 : 0 3-OH and summed feature 3 (C 16 : 1  ω 7c/C 16 : 1  ω6 c) were the predominant fatty acids. Differential characteristics between both strains and their close relatives were also observed. Based on the distinctions in genotypic, phenotypic and chemotypic features, strains 1303 T and 1310 represent members of a novel species of the genus Chitinophaga , for which the name Chitinophaga oryzae sp. nov. is proposed. The type strain is 1303 T (=KACC 22075 T =TBRC 12926 T ).