Abstract: The antioxidant effect of Monascus compounds on liver and kidney of mice and the optimal effective concentration were investigated in the study.Forty Kunming mice （weight 20＋2 g） were randomly divided into 4 groups including control group and three Monascus treatment groups （1 %,3 % and 5 %）. The mice were examined for routine target,blood target,and organ coefficient of liver,and kidney,superoxide dismutase（SOD） activity and malondialdehyde（MDA） levels of liver and kidney were determined.There were no significant differences in routine target,blood target,and the effects of antioxidant and scavenging of radical substance between control and treatment groups. The experiment results indicated that the 1 % Monascus compounds can increase the activity of SOD and reduce the levels of MAD in the mice.