Vibrio harveyi is a kind of important pathogenic bacteria for seawater animals and can bring about severe loss to their culture production. V.harveyi strain GYC1108-1, which was isolated from diseased Pseudosciaena crocea in Zhejiang Province in 2003, was identified after morphological observation, biochemical characteristic analysis, 16sRNA and HSP60 gene sequence detection. Earlier research in our laboratory demonstrated that the extracellular protease（ECPase）was the major virulent factor of GYC1108-1 and was identified as cysteine protease with a molecular mass of 55 kDa as estimated by SDS-PAGE．The protease can decompose the casein of degrease milk and was named as 1108 ECPase．The method of solid LB culture medium containing 1% skim milk was established to detect relative activities of 1108 ECPase and YZ ECPase (YZ is a recombinant bacteria that can express the target ECPase). The optimum cultivation time of GYC1108 1 and YZ excreting ECPase was 36 h and the optimal concentration of ammonium sulfate for ECPase purification was 70% for the above mentioned method．In this study, 1108 ECPase and YZ ECPase were purified by 70% ammonium sulfate and Sephadex G-25 gel filtration for antigens standby. Three different substances A, B and C were chosen to be adjuvants. A was a common adjuvant which was a mixture of white oil and Tween 80; B was propolis adjuvant and C was Freund's adjuvant. The purified 1108-ECPase and YZ-ECPase antigens were mixed with A, B and C before being applied separately to immunize 3 ICR mouse. The adjuvant free and blank treatments were designed as control. There were nine treatments in the immunization test. The immune sera of the mouse were collected after three immunizations. Except the blank control, multi clone antibodies showed high ELISA titers in the sera of eight treatments, which were between 1∶1.6×104～1∶2.56×105. The titers of immune sera in different treatments were ranked as C>A>B>adjuvant free, and it is suggested that the adjuvants chosen followes this effectiveness sequence. The result of Western blot revealed one clear band in ECPase, which had a molecular mass of 55 kDa as tested by mouse anti serum. These results indicated that the prepared 1108-ECPase and YZ-ECPase had good immunogenicity, and this work has provided some basic knowledge for further study on genetic engineering vaccines.