The effects of dietary propionyl triglyceride (PTG) on body weight, serum and hepatic lipids, and the organic acid level in cecum and feces, were investigated in rats. The body weight gain over 14 days in the 5% PTG group was lowest upon comparison with those of the PTG-free (control) and 1% and 3% PTG groups. However, there were no significant differences in food efficiency ratio among the control and PTG groups. The serum cholesterol and triglyceride concentrations in the PTG groups were lower than those in the control group, but the serum HDL-cholesterol concentration was almost the same among the various groups. The contents of hepatic total lipids, total cholesterol, and triglyceride in the PTG groups were lower than those in the control group, but the phospholipid content was higher in the PTG groups. The fecal excretion of neutral steroid was greater in the PTG groups than in the control group. There was little difference in the amounts of organic acids such as acetic, propionic, and butyric acids, except for lactic acid, in the cecal contents and feces among the groups.