Field studies conducted during 2000 cotton growing season in three Governorates, to detect the adult population of the pink bollworm, Pectinophora gossypiella and cotton leafworm, Spodoptera littoralis using funnel pheromone traps. Field generation numbers, life table parameters for field, thermal requirements and heat unit's accumulation was used. Pectinophora gossypiella showed 3 generations in cotton, Spodoptera littoralis was found to have 4 generation in cotton. Generations occurred at an average of 553 and 445 DD's for pink bollworm and cotton leafworm respectively.