In order to examine the effects of exercise training on cholesterol metabolism of arterial wall, male Wistar rats were randomly divided into a sedentary control (n=35) or an exercise group (n=28). The exercise consisted of tradmill running 60 min/day for 5 weeks. After 5 weeks, the rats were injected 2μCi of C-mevalonate per 100g b.w. into peritoneal cavities, and the incorporation of radioactivity into cholesterol of arterial wall was exaimined at various times after the injection. The exercised rats showed a significantly lower of total cholesterol in aortic tissue than did the controls. The incorporation of mevalonate into aorta cholesterol in the exercise trained rats was significantly higher compared with those of the sedentary control group. Since serum lipoprotein uptake in rat arterial wall was increased by exercise training, the decrease in aota cholesterol level observed following exercise seems to be caused by rapid catabolism of cholesterol in the aortic cell.