The effect of amaranth and oat bran on the lipids of blood and liver in rats depending on the kind of fats in diet was the subject of our study. Sixty male Buffalo rats were fed for 28 days one of six diet containing 15% of fat (lard or sunflower oil), 20% of protein and 0.5% of cholesterol. Amaranth and oat bran added to diet provided 4-4.5% of dietary fiber, water soluble fraction of which amounted to 30%. Amaranth significantly decreased the level of total cholesterol in rats blood serum (by 10.7% in the case of diet with lard and by 14% with sunflower oil) and in liver (by 20% in the case of diet with lard and by 23% with sunflower oil). Similarly oat bran decreased the level of total cholesterol in the blood serum: by 19% in the case of diet with lard and by 22% with sunflower oil; and in liver by 22 and 27%, respectively. Amaranth and oat bran did not influence HDL-cholesterol in the blood of rats. The influence of amaranth and oat bran on the concentration of triglycerides in the blood serum depended on the kind of fats in a diet. The diets containing amaranth or oat bran with lard did not decrease the concentration of this lipids, however, the same diets but with sunflower oil decreased this concentration significantly (by 22%). In liver significant hypotriglyceridemic effect of amaranth and oat bran was observed for both of the diets: based on lard and sunflower. The decrease of triglycerides concentration under the influence of amaranth amounted to 10% (diet with lard) and 15% (diet with sunflower oil). Oat bran decreased the concentration of triglycerides in liver by 15% (diet with lard) and 20% (diet with sunflower oil). Sunflower oil added to the diets augmented the hypolipemic effect of amaranth and oat bran.