Cotton, Gossypium barbadense L. is a very important crop in Egypt, and represents a vital source of foreign currency. The present investigation was conducted to determine the effect of three Egyptian cotton varieties; Giza 92, Giza 94 and Giza 96 used for rearing Spodoptera littoralis (Bosid.), on certain biological aspects, at Sakha Agricultural Research Station, under laboratory conditions. Results revealed that larvae fed on Giza 92 and Giza 94 leaves had longer larval duration (21.66 and 20.68 days, respectively) than those fed on Giza 96 leaves (18.16 days). Furthermore, the maximum and minimum pupal durations were recorded on Giza 92 and Giza 96 (10.33 and 6.50 days, respectively). The maximum significant female longevity was recorded on Giza 96 (7.00 days). Also, moths emerging from larvae fed on Giza 96 laid the highest number of eggs (503.66 egg/female) while, the lowest number (300 eggs/female) resulted from moths of larvae fed on Giza 92 variety. The highest larval growth index was observed on Giza 96 (5.23%) followed by Giza 94 (4.43%), and Giza 92 (4.07%). According to this study, biological parameters of S. littoralis on these varieties indicated greater developmental rates and fecundity on Giza 96 and Giza 94, while poorer on Giza 92 variety. So, these results may be used as potential candidates for developing eco-friendly strategies, to manage this pest, through host plant resistance component.