The present studies were undertaken in attempt to investigate the preventive effect of $eta$-glucan from barley ad diltiazem on cholesterol and vitamin D2 induced-atherosclerotic rat. The results obtained were summerized as follows. 1.The group, fed only the mixture of cholesterol and vitamin D2, showed significant increase of calcium, inorganic phosphorus, total cholesterol, lipid LDL-cholesterol and phospholipid in serum, and total lipid in the liver (p<0.05) as comparing with normal group. The aorta showed severe damage of disorganization, necrosis and lipid deposition in the elastic membrane. 2. The group fed mixture of cholesterol and vitamin D2 plus diltiazem simultaneously, showed significant increase of total cholesterol, total lipid and phospholipid in serum, and total lipid and triglyceride n the liver (p<0.05) as comparing with normal group, but the significant decrease of calcium and inorganic phosphorus in serum(p<0.05) as comparing with the atherogenic control group. The aorta showed slight damage of elastic membrane and lipid deposition as comparing with the atherogenic control group. 3.The group, fed mixture of cholesterol and vitamin D2 puls $eta$-glucan simultaneously, showed significant decrease of total cholesterol, LDL and VLDL-cholesterol, total lipid, phospholipid and triglyceride in serum, and total lipid in the liver as comparing with the atherogenic control group(p<0.05), but the significant increase of calcium in serum as comparing with the normal group(p<0.05). The aorta showed no changes in elastic fiber and no lipid deposition in comparing with the atherogenic control group.