To observe the chang of anti\|oxidation, free radicals eliminating and aging postponing in mice induced by a complex anti\|oxidant (pycnogenol grape seeds extracts ginko leaves extracts), the Kunming mice were divided into three dose groups and two control groups, aged mice control groups and young mice control groups, 17 mice in each groups for all. After consecutive administration of the test complex anti\|oxidant by oral injection for 90 days, whole blood and serum were sampled and the MDA contents and SOD activity were determined.Oregon K flies were randomly assigned into four test groups and one control group,400 flies in each groups, male and female in half. Different doses of the test substance were administered. Records of the numbers of the alive and the dead were taken until all flies were dead and LT 50 ,mean life span and maximum life\|span were calculated. The results showed that the serum Malondialdehyde(MDA) was lower and serum SOD activity was higher in high dose groups than those in control group of aged mice. The flies in the group of 0\^06% dose outlived the average expectancy of control group, the LT 50 was high up to 5 days during the survival experiment. These demonstrated that the complex anti\|oxidant had some extent of effects on anti\|oxidation, elimination for free radials and anti\|ageing. Author's address: Zhang Ding, Henan Health and Anti\|epidemic Station, Zhengzhou\ 450003,PRC.