Abstract: The browning phenomenon of water loss and color becoming darker of North Qinglongyi occurs during the storage period from fresh to dry. Studying the mechanism of the browning process can provide a basis for controlling the browning and improving the stability of medicinal materials. The North Qinglongyi fruit peel was used as the experimental material and stored at 4℃. The changes of browning degree (BD), polyphenol oxidase (PPO), phenylalanine ammonialyase (PAL), peroxidase (POD), malondialdehyde (MDA), reducing sugar and Vitamin C (VC) were studied. The experimental data showed that the color of the fruit peel became darker, TP content decreased, PPO activity decreased, PAL activity increased, SOD and POD activity increased first and then decreased, MDA content increased, reducing sugar and VC content decreased. BD, PPO, SOD, POD activity had significantly negative correlation with TP content, and significantly positive correlation with PAL activity, and had no significant correlation with VC as well as reducing sugar. The enzymatic browning and non-enzymatic browning appeared in the storage of North Qinglongyi, the enzymatic browning was the main browning, and PPO might act an important role in enzymatic browning.