Polyphenol oxidase in carambola was partially purified to 21.6-fold with a recovery of 45.2% through chromatographies on DEAE-Toyopearl 650M and Butyl-Toyopearl 650M columns.The purified enzyme quickly oxidized pyrogallic acid,and had no activity towards catechol,resorcinol,hydroquinone and chlorogenic acid.The Km value of the enzyme for pyrogallic acid was 7.92mmol/L.The optimum pH was 8.0,and the enzyme activity was stable with pH in the range of 4.0-11.0.The enzyme had an optimum temperature of 60℃ and was relatively stable at higher temperature:9% of the PPO activity remained after a heat treatment at 90℃ for 30 min.The strongest inhibitors of the enzyme activity were ascorbic acid,followed by NaHSO3 and hydrochloride-L-cysteine.The enzyme was also inhibited by metal ion such as Cu2+,Zn2+ and Ca2+.