Abstract:The contents of total polyphenols and flavonoids and their components of different polar solvents（methanol，ethanol，acetone，ethyl acetate，trichloromethane and petroleum ether） extracts from hawthorn were investigated，and the in vitro antioxidant activities of different extracts and their protective effects on DNA and protein oxidative damage were studied and compared.Results showed that there were differences in the content of total polyphenols，total flavonoids and their biological activities among different hawthorn extracts.Among them，methanol extract showed the highest level of total polyphenols and flavonoids，and also exhibited the strongest scavenging ability on DPPH and ABTS free radicals and ferric reducing antioxidant power.At the same time，the protective effect of methanol extract on DNA and protein oxidative damage were also better than other extracts.Epicatechin，proanthocyanidin B2，chlorogenic acid and quercetin were the main active constituents of methanol extract from hawthorn.The contents of total polyphenols and flavonoids had a high correlation with the antioxidant activity，protective effects on DNA and protein oxidative damage.