The effects of indigestible dextrin on lipids in serum, tissue, and feces were investigated in two experiments carried out with 64 male Sprague-Dawley rats for eight weeks. Experiment I diet(normal fat diet) containing 5% corn oil and experiment II diet(high fat diet) containing 18% fat(13% beef tallow and 5% corn oil) and 1% cholesterol were divided into four groups with 0.5% cellulose(0.5CL : control), 10% cellulose(10CL), 10% Indigestible dextrin I(ID-I) and 10% indigestible dextrin II(ID-II), respectively. ID-I and ID-II diets produced a decrease in serum total lipid and cholesterol concentrations in both normal and high fat diets but more significantly in the groups fed high fat diet. ID-I, ID-II, and 10CL of high fat diet decreased serum glucose concentration. ID-I and ID-II diets also decreased liver cholesterol and triglyceride concentrations in rats fed normal and high fit diets. The fecal excretion of cholesterol in ID-II/high fat diet was significantly higher than that of 0.5CL diet. Bile acid excretion was increased in the rats fed 10CL and ID-II diets of normal and high fat diets. These observations indicat the hypolipidemic and hypocholesterolemic effects of indigestible dextrin on the rats. These effects are mediated by the increase of facal cholesterol and bile acid excretion. (Korean J Nutrition31(6) : 981-990, 1998)