Abstract: This study aimed to reveal the distribution characteristics of phenolics and polyphenol oxidase in different fruit parts and fruit browning at the frozen storage. The total polyphenols content, chlorogenic acid content and polyphenol oxidase activity of flesh and peel of Qinghai excellent local pear variety ‘Ruaner pear’(Pyrus ussuriensis Maxim) fruit were determined by using HPLC and spectrophotometry at three periods: ripening (room temperature), frozen (-18℃) and thawing (at room temperature). The results showed that the total phenols of flesh were more than that of peel and polyphenol oxidase was the opposite after ripening; the total phenols and polyphenol oxidase of different parts increased for different degrees, and chlorogenic acid of peel declined sharply while that of flesh increased slightly in frozen storage process. After thawing, the total phenols and polyphenol oxidase of different parts decreased obviously while chlorogenic acid of peel changed slightly. The distribution of polyphenols and polyphenol oxidase were unevenly regionalized in different parts of Ruaner pear after fruit ripening, and frozen storage exacerbated the accumulation of polyphenols and polyphenol oxidase activity and led to peel browning at frozen storage.