The effect in degree of saturation and unsaturation of dietary added oils on the serum cholesterol level in the rabbit was studied for a kperiod of 4 weeks using isocalories and isonitrogenous diets. The subject rabbits were divided into 10 feeding groups such as control-1 (Basal diet only), A group (Basal+sesame oil), B group (Basal+perilla oil), C group (Basal+soybean oil), D group (Basal+rice bran oil), Control-A(Basal+casein), A-1 group (Basal+sesame oil+ casein), B-1 group (Basal+perilla oil+casein), C-1 group (Basal+soybean oil+casein) and D-1 group (Basal+rice bran oil+casein). The results are summarized as follows: 1. Body weight gains per week of the perilla oil fed group were higher than anyother groups during the experimental period. 2. Food efficiency ratios for the group of perilla oil fed were 1.041, 0.781, 0.520 and 0.431 for 1st, 2nd, 3rd and 4th week, respectively. 3. In the group of perilla oil and Casein fed, food efficiency ratios for the experimental period were 0.887, 0.823, 0.489 and 0.437 for 1st, 2nd, 3rd and 4th week, respectively. 4. It is investigated that the food efficiency ratio for perilla oil fed groups was higher than the group of perilla oil and casein fed. 5. Calorie efficiency ratios for perilla oil fed group were 0.018, 0.036, 0.024 and 0.020 for 1st, 2nd, 3rd and 4th week, respectively. Calorie efficiency ratios for perilla oil and casein fed group were 0.028, 0.030, 0.024 and 0.020 for 1st, 2nd, 3rd and 4th week, respectively. 6. Serum cholesterol was 72.8mg% for the group of perilla oil (6gr) and casein(6gr) fed, and liver cholesterol was 460.5mg% for the same group. 7. Serum triglyceride was 130.7mg% for the group of perilla oil (6gr) and casein (6gr) fed. 8. Blood glucose was 40.34mg% for control-l and 96.4mg% for control-A, respectively. Blood glucose was 120.4mg% for group Band 1l0.7mg% for group B-1, respectively. 9. The degree of saturation/unsaturation for perilla oil (SFA/USFA) was 7.8/92.2 and nonessential fatty acid/essential fatty acid(NEFA/EFA) was 26.3/73.7. In this conditions, serum and liver cholesterol was lower than anyother conditions for this experimental period. 10. For the perilla oil fed group, serum cholesterol was 105.5mg% for pleic acid/linoleic acid(18.5/58.5) and 72.8mg% for linoleic acid/linolenic acid(15.2/58.5). In this group, triglyceride was 132.5mg% for oleic acid/linoleic acid and 130.5mg% for linoleic acid/linolenic acid. 11. There are positive correlation between serum cholesterol and saturated fatty acid $({\gamma}=0.78)$, and unessential fatty acid $({\gamma}=0.41)$. There are negative correlation between serum cholesterol and unsaturated fatty acid$({\gamma}=-0.78)$ and essential fatty acid$({\gamma}=0.77)$, respectively. 12. The range of most effective diet for serum cholesterol level lowering was nonessential fatty acid/essential fatty acid(26.3/73.7), saturated fatty acid/unsaturated fatty acid(7.8/92.2) and added oil (6gr)/added casein protein(6gr).