A bacterial strain designated RZ03T was isolated from an intertidal sand sample from the Yellow Sea in China and characterised using a polyphasic taxonomic approach. Cells of strain RZ03T were observed to be Gram-stain negative, aerobic, and oxidase and catalase positive rods showing gliding motility and forming yellow colonies. Growth was found to occur at 7-30°C (optimum, 25°C), at pH 5.5-9.5 (optimum, pH 6.5-7.0) and with 0.5-5% NaCl (optimum, 1.5-2%). Phylogenetic analysis based on 16S rRNA gene sequences indicates that strain RZ03T clusters within members of the genus Flavivirga of the family Flavobacteriaceae and is closely related to the type strains Flavivirga amylovorans JCM 17112T and Flavivirga jejuensis JCM 17113T (97.9% and 97.5% similarity, respectively). The predominant cellular fatty acids are iso-C15:0, iso-C15:1 G, iso-C17:0 3-OH and iso-C15:0 3-OH and the major respiratory quinone is MK-6. Polar lipids include phosphatidylethanolamine, three unidentified aminolipids, an unidentified phospholipid and four unidentified lipids. The genome of strain RZ03T is 4.88 Mbp with a G+C content of 32.2mol%. A total of 4152 genes are predicted, with 4052 protein-coding genes, 51 RNA genes and 49 pseudogenes. This polyphasic study suggests that strain RZ03T represents a novel species in the genus Flavivirga, for which the name Flavivirga rizhaonensis is proposed. The type strain is RZ03T(= KCTC 62833T = MCCC 1K03615T).