Abstract: We studied the polyphenol oxidase activities of Corilus versicolor cultured in PDY fluid medium. The peak of enzyme production appeared on the 14th day for polyphenol oxidase at the constant temperature of 30℃ and with vibration of 110 r/min, the maxmum enzyme activity was 549.0 unit. The optimum condition was 30℃ and pH 5.0 for polyphenol oxidase. Mn2 +, Ba2 + and Mg2+ were activators for polyphenol oxidase, where as Fe3+ and Ag+ were inbihitors.