In order to observe the effects of the fees mixed with the lard and two vegetable seed oils on the fatty acid compositions of liver and brain tissue, the oils mixed with 2.5% lard and various levels of perilla oil and evening primrose oil were administered to the male rats of the Sprague-Dawley for 4 weeks . In the fatty acid composition of liver lipid, saturated fatty acid (SFA) contents were rich in the phopholiipide and cholesteryl ester fraction. Monounsaturated fatty acid (MUFA) contents were rich in the triglyceride fraction and polyunsaturated fatty acid (PUFA) contents were rich in the phospholipid fraction. In the fatty acid composition of liver lipid fractions, according as the contents of mixed perilla oil decreased and the contents of mixed evening primrose oil increased , n -3 PUFA contents tended to decrease and n-6 PUFA contents tended to increase. Fatty acid composition of liver lipid fractions were influenced from the fatty acid composition of the test lipids. In the fatty acid composition of brain phospholipd, PUFA contents (40%) were rich and according as the contents of mixed evening primrose oil increased, the ratio on n-3/n-6 PUFA and eicosapentaenoid acid (EPA) /arachidonic acid (AA) tended to slightly decrease.