The yields of solvent fraction of irradiated red ginseng powder were increased in the order of petroleum ether(PE)<diethyl ether(DE)<ethyl acetate(EA)<N-butanol(BU)<aqeous fraction(AQ), and did not show any changes in fraction yidlds by irradiation dose levels. Inhibition activities of lipid peroxide formation were increased in the order of AQ BU<PE<DA<DE. Inhibition activities of malonaldehyde formation were increased in the order of AQ<BU<EA<PE<DE. AQ fraction showed little effects on the antioxidative activity and all the activities of the samples did not changed by gamma irradiation. The reverse mutation assay using Salmonella typhimurium (TA98, TA100 AND TA102)demonstrated that the nonirradiated and irradiated red ginseng powder extract did not have mutagenic activity (presence of S9 mix or not). The chromosomal aberration test in mammalian animal cell (Chinese hamster lung fibroblast, CHL) showed no significant increase in incidence of structural and numerical aberrations, comparing gamma-irradiated red ginseng powder extracts to nonirradiated red ginseng powder extract in the concentration of the sample production cytotoxicity(presence of S9 mix or not). Therefore, gamma-irradiatied red ginseng powder (upto 10 kGy) could be safe on the genotoxic point of view.