This study investigated the impact of some insecticides belonging to pyrethroids (cyper guard, lambadasetra, debemethrin),organophosphates (pestban, diazinon setra) and pyrazole (hatchi hatchi) on the biochemical aspects in two insects the 4th instar larvae of cut worm, Agrotis ipsilon and the 9th instar larvae of red palm weevil Rhynchophorus ferrugineus. The activities of three vital enzymes and total protein (TP) were laboratory tested at LC50 concentration. This enzymes were amylase, chitinase and protease. Results showed that tested insecticides lead to decrease the activity of amylase and chitinase enzymes. On the other hand, the level of total protein and activity of protease enzyme were increased after treatment 4th instar larvae of A. ipsilon with the LC50 for each compound. While, in 9th instar larvae of R. ferrugineus tested compounds caused increase in the activities of amylase, chitinase and protease enzymes. On contrary the tested compounds caused decrease in the total protein content. In general, tested insecticides were significantly affected on activities of enzymes and total protein compared with control.