Authors have isolated phages of V. parahaemolyticus from shellfish and investigated some of their characteristics. The results obtained were as follows: Twenty-three phage strains(9.2%) out of 250 specimens were isolated. Plaques of phages were small, clear or turbid and $0.5{sim}1.5mm$ in diameter. The electron micrographs of K3 phages showed two morphology; one was a hexagonal head about 105nm with a tail about 12nm, the other was a hexagonnal head about 60nm with a tail about 25nm. The host ranges of pahges were limited to V. parahaemolyticus strains and there appeared to be no relationship between the K serotypes of V. parahaemolyticus strains and the host ranges of the phage isolates. The adsorption rate of phages were more than 80% for $10{sim}15$ minutes, the inactivation rate at $60^{circ}C$ was more than 99% for $40{sim}45$ minutes. The pH stability range was between 6.0 and 8.0. The inactivation rate of phages by UV irradiation was more than 99% for $45{sim}75$ seconds.