Abstract: The research was carried out to study the effect of gamma irradiation on chemical composition as well as to investigate its effect on protein quality. Seeds of Giza cultivar of dry bean phaseolus vulgaris were treated with gamma irradiation at dose levels of 1, 1.5 and 2 k Gys. The results indicate that slight change was observed in proximate Composition and ash minerals of dry bean flour as affected by gamma irradiation. However for protein fraction gamma irradiation caused Significant decrease (p<0.05) in albumins while no significant change was observed for globulins, gliadins, glutenins and residue fractions. On the other hand the in vitro protein digestibility was not significantly changed while protein solubility was significantly (p<0.05) decreased. The results also revealed that gamma irradiation caused no significant change for water holding capacity, bulk density, emulsion activity, emulsion capacity and foaming capacity however oil absorption capacity and foaming stability slightly decreased by application of gamma irradiation.