A Gram-reaction negative, aerobic, motile, non-pigmented and rod-shaped bacterium, designated as 168GH5-2-16(T), was isolated from seawater Jeju island. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that the strain formed a distinct lineage within the genus Vibrio and was most closely related to Vibrio variabilis R-40492(T) (96.0%). The DNA G+C content was 49.3 mol%. The major polar lipids were phosphatidylethanolamine (PE) and phosphatidylglycerol (PG). The predominant quinone was ubiquinone-8 (Q-8). The major fatty acids were C-16:0, summed feature 3 (comprising C-16:1 omega 7c/C-16:1 omega 6c) and summed feature 8 (C-18:1 omega 7c/C-18:1 omega 6c) supported the affiliation of 168GH5-2-16(T) to the genus Vibrio. Moreover, the physiological, biochemical, and taxonomic analysis allowed the phenotypic and genotypic differentiation of strain 168GH5-2-16(T) from the recognized species of the genus Vibrio. Therefore, strain 168GH5-2-16(T) represents a novel species of the genus Vibrio, for which the name Vibrio hannami sp. nov. is proposed, with the type strain 168GH5-2-16(T) (=KACC 19277(T) = DSM105032(T)).