Polyphenol oxidase (PPO) is the key enzyme leading to browning of Agaricus bisporus (A.bisporus).In order to determine the influence of UV-C treatment on polyphenol oxidase (PPO) of A.bisporus (Cv,192),visual quality and color,degree of browning,PPO activity and the expression of PPO genes in different tissues of A.bisporus during cold storage after 1.0 kJ/m2 UV-C treatment.Results showed that the degree of browning and PPO activity of A.bisporus increased during 21 d of storage at 4℃.UV-C treatment increased the PPO activity and exacerbated the browning of cap surface of A.bisporus during the beginning period of the storage.