The ethanol extracts of flowers from Abelmoschus manihot was extracted by petroleum ether、ethyl acetate and n-butyl alcohol, and four different polar portions were obtained. The scavenging effect of different phases on DPPH·, ·OH and H₂O₂ were studied to research the antioxidant activities of each phase. Moreover, the protection of n-butyl alcohol phase on DNA oxidative damage was also studied, and the flavonoids component was identified by HPLC-MS. The results showed that the ethyl acetate phase had the best scavenging effect on DPPH·, with IC₅₀ value 0.038 6 mg/mL. However, the n-butyl alcohol phase had scavenge ·OH and H₂O₂ best, and the IC₅₀ values were 0.225 0 and 0.575 7 mg/mL, respectively. The n-butyl alcohol phase was proved to show protective effect in some degree on DNA oxidative damage., and totally 11 kinds of flavonoids were found in the n-butyl alcohol phase.