Effects of fermented milk were tested in Sprague-Dawley male rats. In six treatment 150 rats were fed for 12 months: (1) normal control synthetic pellets+water, (2) cholesterol control synthetic pellets containing 1% of cholesterol and 500, 000 IU of vitamin D2/100 g (cholesterol pellets) +water, (3) cholesterol pellets+25% fermented milk, (4) cholesterol pellets+50% fermented milk, (5) cholesterol pellets+75% fermented milk, (6) cholesterol pellets+100% fermented milk. In 3, 6, 9, 12 months, rats were sacrificed for analysis of samples. Rats received the fermented milk had significantly lower (p<0.05) serum cholesterol levels and higher ratios of HDL-cholesterol to total cholesterol than did the water fed rats. Stomach, heart, abdominal aorta and kidney of rat from fermented milk group showed slighter calcification or necrosis than did those of rat from cholesterol control group. Weight gain, diet intake, and drink consumption were significantly different among groups. Results indicate that fermented milk had a helpful effect of experimental hypercholesteremia and atherosclerosis.