The antioxidative and hypolipidemic effects of barley leaf essence (BL) were investigated in a rabbit model of atherosclerosis. Twenty-four New Zealand White male rabbits were assigned randomly into four dietary groups. The normal group was fed regular rabbit chow and the control group was fed a chow containing 0.5% cholesterol and 10% corn oil. The BL group and the probucol group were fed the same diet as the control group plus 1% (w/w) BL or 1% (w/w) probucol, respectively. The plasma levels of total cholesterol, triacylglycerol, lucigenin-chemiluminescence (CL) and luminol-CL were increased in the control group compared to the normal group; and they were decreased in the BL group and the probucol group compared to the control group. The value of T50 of red blood cell hemolysis and the lag phase of low-density lipoprotein oxidation increased in the BL group and in the probucol group compared to the controls. Ninety percent of the intimal surface of the thoracic aorta was covered with atherosclerotic lesions in the control group, but only 60% of the surface was covered in the BL group. This 30% inhibition of hyperlipidemic atherosclerosis by BL was associated with a decrease in plasma lipids and an increase in antioxidative abilities (as measured by T50, lag phase and CL). These results suggest that the antioxidant and hypolipidemic effects of BL could be useful in the prevention of cardiovascular disease in which atherosclerosis is important.