This study was undertaken to determine whether dehulled defatted flour has an effect on postprandial plasma lipoprotein composition, hepatic lipid composition, enzyme and hormone levels in rats. Control(casein) and experimental (dehulled defatted soy flour)diets were fed to rats for 7 weeks. all animals (S. D. rats, male) were sacrificed 2 hrs after the feeding of 5g of each diet. Defatted soy flour feeding significantly lowered postprandial plasma total cholesterol, chylomicron/VLDL-cholesterol, hepatic cholesterol and triglyceride(TG) as compared with casein feeding, whereas no significant effect on plasma TG was observed. Intestinal kipase activity was elevated , whereas trypsin activity was suppressed in the dehulled defatted soy flour group. Plasma glucagon, thyroid hormone and hepatic HMG-coA reductase levels were not affected by diet treatment. These results hypothesize that dehulled defatted soy flour affects cholesterol digestion and absorption in guts, thus delaying the appearance of chylomicron cholesterol in plasma or affecting the disappearance of chylomicron remnant to high-density-lipoprotein(HDL).