Objective:To evaluate the capability of 6-hydroxykaempferol-3-O-β-glucoside(6-HK-3-O-G) for inhibiting Fenton reaction and scavenging hydroxyl free radicals,and to explore the inhibitory mechanism on Fenton reaction.Methods:A model to test oxidative damage to deoxyribose and a reaction system to test DPPH free radical scavenging activity were created.Results:6-HK-3-O-G not only had strong scavenging activity against hydroxyl free radical,but also could protect 2-deoxyribose against oxidative damage caused by Fenton reaction.The underlying mechanisms were related to the direct scavenging of hydroxyl free radical generated from Fenton reaction but seemed to be mainly due to the chelation of 6-HK-3-O-G with Fe2+,thereby blocking Fenton reaction.Conclusion:6-HK-3-O-G has strong anti-oxidation activity,and the chelation of 6-HK-3-O-G with Fe2+may play a vital role for its inhibiting Fenton chemistry under physiological conditions.