The objective of this study was to investigate the effect of autoclaving and different doses of gamma irradiation on the apparent ileal digestibility of amino acids of cottonseed meal in male broiler breeders. Samples were irradiated in a gamma cell at total doses of 15, 30 and 45 kGy. One package (control) was left at room temperature: Similar to the other treatments, evaporation decreased the moisture content of the samples. Autoclaving of cottonseed meal for 15 min at 121°C was studied. The treatments were: (1) control, untreated cottonseed meal diet; (2) autoclaved cottonseed meal diet; (3) cottonseed meal diet gamma irradiated at a dose of 15 kGy; (4) cottonseed meal diet gamma irradiated at a dose of 30 kGy; (5) cottonseed meal diet gamma irradiated at a dose of 45 kGy. The results show that autoclaving for 15 min at 121°C did not have a statistically significant effect on the apparent ileal digestibility of the amino acids in cottonseed meal when compared with the control treatment. The results also show that gamma irradiation of cottonseed meal were not effective in increasing the apparent digestibility of amino acids. In addition, irradiation of cottonseed meal did not improve the apparent digestibility of amino acids in comparison with the other processing methods only, but also significantly decreased it (p<0.05).Key words: Gamma irradiation, digestibility, amino acid, cottonseed meal, broiler