This experiment was conducted on cotton Gossypium barbadense L. on two localities in Behira and Beni-Sueif governorates through the period from June to September of two successive cotton seasons 2014 & 2015 to evaluate the performance of sex pheromone and light traps for studying the population of Earias insulana under insecticide application. The tested varieties were Giza 70 and Giza 88 at Behira governorate and Giza 80 at Beni-sueif governorate. Data revealed that the larval population density increased during August on both check and treated plants through the two seasons in the two governorates. Larval population density was higher in check plants than on treated ones. Also data clearly showed that the moth population density was higher in the pheromone traps than in the light traps in spite of the moths were male only. The highest adult population density was recorded in Giza 80 at Beni-sueif governorates at 29.3 °C & 48 % R.H in 2014 season and 31.5 °C & 52.8 % R.H in 2015 season. Statistical analysis revealed significant differences among the cotton varieties, where the lowest larval population density was recorded on Giza 88 (12.9) followed by Giza 70 (14.8) in Behira governorate at an average of 24.1°C & 65 R.H in 2015 season.