Abstract: This experiment was conducted to evaluate the using of different levels of cottonseed meal with and without ferrous sulfate in broiler diet. The performance of 42 old day straight Cobb (500) broiler chicks fed diets containing 5, 10, 15 and 20% Cottonseed Meal (CSM) was compared with that of control chicks fed corn and soybean meal based broiler rations. Four dietary treatments with Ferro sulfate, four dietary treatments without Ferro sulfate. The 1 treatment (control) 2-5 (without Ferro sulfate) and 6-9 (with Ferro sulfate). All diets were formulated to meet minimum NRC requirements. Lysine levels were adjusted by addition of synthetic lysine at rates of 0.5% of the protein in CSM and by addition of synthetic Ferro sulfate at rate of 0.04% of the protein in CSM.