This study was conducted to investigate the effect of LC₅₀concentration of three commercial bio insecticides; viruset, spodopetra littoralis nuclear polyhedrosis virus, protecto Bacillus thuringensisvar. kurstakiand their mixture profect on the protein profile and enzyme activity of three carbohydrate digestive enzymes (amylase, invertase and trehalase).The digestive enzymes were determined in 6^th larva linstar after treatment of 3^rd larval instar with the LC ₅₀ concentration. Results showed that amylase activity was relatively un affected in treated larvae with viruset and protecto,but there was asignificant decrease when treated with profect compound.On the other hand the activity trehalase was significantly decreased in all samples. Also protein profile of the treated and untreated larvae was studied by SDS –PAGE technique. Results showed that the protein pattern of larvae treated with the profect compound leads to inhibition and appearance of some bands followed by protecto compound, while viruset has a slight change in the pattern. Thus, our findings indicated that among the three tested compounds, profect compound showed a highest significant effect on both protein profile and enzyme activity of the larvae.