Abstract: s With litchi( Litchi chinensis Sonn. cv. Huaizhi) as material, changes of polyphenol oxidase and peroxidase activities and their isozymes and the relation of these to the litchi pericarp browning during storage were studied. The results indicated that, the polyphenol oxidase and peroxidase in litchi pericarp had two forms, free form and bound form. Their activities all changed during cold storage, and some new isozymes bands of polyphenol oxidase and peroxidase appeared along with litchi pericarp browning. There is some relation between these two enzymes and the litchi pericarp browning.