This study demonstrates that red yeast rice exhibits radical scavenging and antihypercholesterolemic activities in rats fed cholesterol. Sprague-Dawley male rats were divided to five dietary groups (normal, chol-control; and M-1, M-2 & M-3 administered 150, 300, and 500 mg/kg red yeast rice, respectively) and fed their respective diets for 4 weeks. No significant differences in food efficiency ratio (FER) were found among the five groups. The weight of perirenal fat pads decreased with increasing amounts of red yeast rice supplementation. There was a significant decrease in the levels of cholesterol in M-3 group fed red yeast rice with 500 mg/kg compared to those in the chol-control, M-1 and M-2 groups (p<0.05). Among the rats fed the cholesterol-enriched diet, all groups fed red yeast rice showed higher concentration of the HDL cholesterol, but lower concentration of the LDL cholesterol than those of the chol-control group. The scavenging activity of the methanol extract from red yeast rice was increased with increasing amounts of the extract. The glutathione content in the normal group and in the M-3 group were higher than that in the other groups. The M-3 group showed similar hepatic glutathione contents to those of the normal group. These results suggest that red yeast rice may be safe and effective for lowering serum levels of total and LDL-cholesterol, ratio of non-HDL/HDL, and severity of experimental atherosclerosis.