Attempts for degossypolization of the solvent extracted Egyptian cottonseed meal (CSM) and evaluation of its nutritional value as a possible protein supplement for human feeding were undertaken. Three methods were applied for degossypolization: Steaming, addition of iron(II)-sulphate dihydrate, and steaming after addition of iron(II)-sulphate dihydrate. Steaming was done for varying periods of time. Nutritional evaluation was undertaken by chemical analysis and by feeding experiments. Chemically, the third method for degossypolization was the most effective. Feed efficiency and protein efficiency for diets containing 15 and 10% levels of CSM protein indicated that all treatments used for detoxification caused a decrease in diet and protein quality. Diets containing iron-supplemented CSM at the same level were the best of all. Mixing CSM with casein to form a diet containing 10% protein increases the protein quality of both casein and CSM.