The effects of soybean products(bean curd and curd residue) on the cholesterol profiles of serum and liver were studied in rats. Male rats were fed on purified diets, supplemented with cholesterol, containing casein (CAS), dried bean curd(DBC), or mixture of casein and dried bean curd residue(CBCD, 3:1, w/w) as a protein source for 4weeks. Dietary DBC and CBCD, compared with CAS, reduced markedly the concentration of serum cholesterol. The concentration of HDL-cholesterol was significantly higher in the CAS group than in the CBCD group, but there were no significant differences in the ratio of HDL-cholesterol to total cholesterol. Liver cholesterol was lower in the DBC group than in the CAS and CBCD groups. The results suggest an effective cholesterol-lowering action of soybean products in rats fed on cholesterolemic diets, and further a possibility that than curd dreg decrease the concentration of serum cholesterol, regardless of the presence of animal protein in diets.