The present investigation aimed to clarify the changes in the enzymatic activities of the Pinkbollworm larvae treated with some biopesticides. Data showed that Abamectin( 1.8%EC ) is the most effective than Spinosad (24%SL ) on the third instar larvae of the pink bollworm (pectinophora gossypiella) (Saund) followed by Esfenvalerate (20%EC) and Dipel 2x (6.4%WP) (Bacillus thuringiensis) respectively. The LC50 of Abamectin, Spinosad, Esfenvalerate and Dipel 2x caused increasing effect in protein concentration, reaching 28.8, 25, 48.9 and 39.1% respectively in gut tissue of larvae after 6 hrs. of treatment. After 24 and 48 hrs. of treatment this content was decreased in Dipel 2x and Abamectin by 33.1, 33.5% and 39, 26.3% respectively. But the treatment of Spinosad and Esfenvalerate increased the protein by 26.2, 13.2% and 18, 16.2% respectively. Great increase in activity of protease and glutathione-s-transferase enzymes was recorded in larvae after all intervals of treatment by the tested pesticides. A high inhibitions in the activity of ATPase in larval tissues after all intervals of treatment except Abamectin and Esfenvalerate after 48 hrs. of treatment were occurred. A Significant increase in acid and alkaline phosphatase activities was detected in 6hrs. treatment of the four insecticides, but this response was changed after 24 and 48hrs. of treatments .