This study was carried out to determine the effects of sodium alginate and cellulose on the cholesterol metabolism in cholesterol-fed rats. Thirty male Sprague-Dawley rats were randomly assigned to three dietary treatments. Rats were fed, ad libitum, diets containing 10% dietary fibers as sodium alginate, cellulose or fiber-free with 1% cholesterol for 4 weeks. The results obtained were as follows: the feeding of sodium alginate with 1% cholesterol induced a significant decrease in plasma cholesterol and TG. The feeding of sodium alginate significantly decreased hepatic total lipids and TG levels, whereas the feeding of sodium alginate significantly increased hepatic HMG-CoA reductase activity. The feeding of sodium alginate and cellulose significantly increased fecal cholesterol and bile acid excretion. The excretion of TG in sodium alginate group, however, was two-fold and four-fold increased compared to cellulose and fiber-free group, respectively. As a result of this study, the ingestion of sodium alginate decreased plasma cholesterol and TG concentrations and liver TG concentration. This may be explained by the facts that fecal cholesterol, bile acid and TG level were increased significantly in sodium alginate group. The increased hepatic HMG-CoA reductase activity by sodium alginate feeding appears to be corresponded to whole-body cholesterol homeostasis.