A feeding trial was conducted for fattening Awassi male lambs using olive take to study the nutritional effect of this by-product and to search for low cost rations. Fifty male lambs were assigned to five dietary treatments. The control diet was composed of 77 % barley (whole grain), 12 % wheat bran, 9 % soybean meal, 0.5 % dicalcium phosphate, 0.5 % sodium chloride, 0.1 % mineral and vitamin premix and 0.9 % sand. To each ration of the other four treatments, olive cake was incorporated instead of barley at a level of 10 %, 120 %, 30 % and 40 % respectively. Urea was added at the rate of 1 % in these four treatments instead of a part of the soybean meal. The lamb feeding trial extended for a period of 63 days. Average initial live weights were 30.9, 33.0, 29.7, 30.5 and 32.8 kg for each of the five groups, respectively. Means of the daily gains were 246, 206, 198, 143 and 143 g per day for each of the five groups respectively with the fourth and the fifth groups being significatively different from the three others. Average feed conversion rates were 5.93, 6.35, 6.70, 9.38 and 9.31 kg feed per kg day gain and the feeds costs per kg gain were 3.10, 3.15, 3.12, 4.18 and 3.89 NIS (New Israeli Sheqel) for each of the five treatments, respectively. The result of the experiment indicated that the different olive cake levels had no effect on the distribution of lean, fat or bone weights among the wholesale cuts. This experiment shows that, under current feed prices in the West Bank, replacing up to 20 % of barley with olive cakes proves to be beneficial and economically feasible.