We studied the influence of different quantities of fat in the diet (sunflower oil, pork fat) on the fat content in hepatic tissues of the rat. 20g of fat were given comprising 44% of the total energetic value of the diet. The study was done in male rats of the Wistar strain, 2 months old at the commencement of the experiment. The study lasted 6 months. The results showed that the saturated fatty acid content of the liver (16:0; 18:0) was higher in animals who were fed with sunflower oil. The content of unsaturated fatty acids (18:2; 18:3, 20:4) was higher in the liver of animals fed on pork fat. The content in dokosaheksaenic fatty acid (22:6) was higher in the hepatic tissue of the animals fed with pork fat.