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To evaluate the changes of total phenolic content and antioxidant capacities of five peach cultivars, this work measured them separately in extractable polyphenols and non-extractable polyphenols during the last month of ripening. Total phenolic content was detected using the Folin-Ciocalteau reagent, while total antioxidant activity was detected by DPPH and FRAP assay. In addition, the contribution of extractable polyphenols and non-extractable polyphenols to the total antioxidant activity of peaches was investigated. It is noted that ripening caused a decrease of total phenolic content associated to extractable polyphenols and non-extractable polyphenols by 45.1％–74.6％, 20.7％–41.7％, respec-tively. Additionally, total antioxidant activity decreased over the ripening period with a high correlation with total phenolic content. Extractable polyphenols contributed more than 50％ to the total antioxidant activity, while the non-extractable antioxidants contributed around 31.3％–45.7％(DPPH) or 12.6％–25.4％ (FRAP), which suggests that the antioxidant properties of peaches may be undervalued in previous researches.