Larval stage of Earias insulana (Boisd.) and Pectinophora gossypiella (Saund.) were exposed to gamma radiation doses (50&500 Gy). In addition, emamectin benzoate and triflumuron were exposed to the same doses for potentiating purpose. Lethal, biological and life table aspects were observed to evaluate gamma radiation effecting on P. gossypiella treated as newly hatched larvae with tested compounds alone or exposed to gamma doses. First and second instars of E. insulana was more susceptible to gamma radiation than 3^rd and 4^th larval instars as well as P. gossypiella newly hatched larvae was more susceptible instar to gamma doses than 4^th instars larvae susceptibility. Dose of 500 Gy caused the higher potentiating lethal effect for emamectin benzoate against P. gossypiella treated as newly hatched larvae that reached to complete death in larval stage as well as dose of 50 Gy comparing with triflumuron lethal potentiating effect. Biological and life table aspects were affected by triflumuron +500 Gy that was the most potent compound effect on the most biological and life table aspects, followed by triflumuron + 50 Gy, emamectin benzoate and triflumuron when used singly.