This study compared the phenotypes of Aspergillus flavus CMT 00079 inoculated in peanut grains after induction of Cs 137 gamma radiation and electron beams. Peanut grains were distributed in Petri dishes and inoculated with the fungal strain and incubated in a BOD germination chamber at 25ºC for 5 days. After 24 hours, the plates were irradiated with Cs137 and absorbed doses of 1.0 KGy with 0.5kGy increase to 8.0 KGy. In electron beam irradiation the absorbed doses were 6.0; 7.0; 7.5 and 8.0 KGy. In both sources the standard 0 KGy plate was maintained. The inactivation doses of Cs 137 strains ranged from 4.5 to 8.0 KGy and with electron beam from 6.0 to 8.0 KGy. Between days 1; 7; 15 after irradiation. Within 15 days after irradiation the subcultures in isolated and irradiated nutrient medium recovered their fungal growth from 1 to 7.5 KGy with CS 137 and 6.0 to 7.5 KGy with electron beam. The results showed that the absorbed dose of 8.0 KGy was sufficient to inactivate or eliminate Aspergillus flavus.