A hemolysin producing strain was isolated from Kum rivet estuary located in west part of Korea. In the process of identification the isolated strain was similar to V. mimicus but did not show characteristics of known Vibrio species; therefore, the strain was designated as Vibrio sp. D9 ( V. kumkang) tentatively and further identification study was carried out by comparing its bacteriological characteristics, Morphologically Vibrio sp. D9 was a typical straight roe with a polar flagellium. Among known Vibrio species no identical strains were found when using automatic bacteria identification system ($MicioLog^(TM)$system, release 4.0, Biolog Inc., USA) which evaluated the ability of metabolizing 95 kinds of carbon and nitrogen sources. Vibrio sp. D9 showed 18 and 13 different responses as compared to V. mimicus and V. cholerae, respectively. Clear hemolysis zones were observed with the strain against human and sheep blood agar plate, Hemolytic toxicity was confirmed by strong vascular permeability and fatal toxicity against mouse was also observed. Thus the strain was a pathogenic vibrio. Growth conditions for Vibrio sp. D9 were salinity of $0{~}5.0{\%}$, pH of $6.4{~}9.8$, temperature of $15{~}41^{circ}C$, respectively.