[en] γ irradiated rutin and baicalin ethanol solutions saturated with air were eluted through alumina columns and the G values of hydrogen peroxide generated in the solutions were measured. Different results from former works were obtained and the reasons of the difference were discussed. A precise method was established as follows: hydrogen peroxide should be separated from flavonoids by passing the flavonoids ethanol solution through alumina columns before the measurement and the amount of hydrogen peroxide generated from self-oxidation of the flavonoids should be deducted. Under a dose rate of 6.93 Gy min^-1, the G values of hydrogen peroxide in γ irradiated rutin and baicalin ethanol solutions saturated with air were determined to be 5.5 +- 0.2 and 7.3 +- 0.2, separately. After irradiation of rutin-and baicalin-O₂-ethanol solutions, the G values of hydrogen peroxide were increased comparing with that of pure ethanol-O₂ solution