Abstract:The main components and antioxidant activity of Prunus cerasifera Jiaosu were studied.Six Jiaosu samples were prepared by fermentation with P.cerasifera pulp or skin supplemented with different proportions of rock sugar.The content of total flavonoids，total sugars，total phenols，total acids，and soluble solids，as well as the DPPH radical scavenging ability，hydroxyl radical scavenging ability，and total antioxidant capacity，of the samples was determined before and after fermentation，and their correlations were analyzed.The results showed that all the six Jiaosu samples had obvious antioxidant activity.The pulp Jiaosu（R30）and skin Jiaosu（P30）with the addition of 30% sugar showed the strongest DPPH radical scavenging ability，hydroxyl radical scavenging ability，and total antioxidant capacity，which were higher in R30 than in P30.Compared with the un-fermented samples，R30 and P30 showed 62.57% and 48.28% decreases in total flavonoids，569.81% and 502.89% increases in total sugars，217.01% and 172.25% increases in total phenols，134.28% and 99.17% in total acids，and 182.53% and 202.40% increases in soluble solids，respectively.The hydroxyl radical scavenging ability and total antioxidant capacity were positively correlated with the content of total phenols and total acids（P＜0.01）.The addition of a suitable amount of exogenous sugar can improve the quality of P.cerasifera Jiaosu.