The insecticidal activity of three commercial Bt – formulations and one fungus; namely DipelDf , W- Bus and Protecto (Bacillus thuringiensis var.kurstaki ) and Biofly ( Beauveria bassiana) were tested against 2^nd and 4^th instar larvae of Spodoptera littoralis (Boisd) and Hypera brunneipennis (Boheman) were studied  under laboratory conditions. Results revealed that Bt- formulations caused the larval mortality after treatment of S. littoralis 2^nd and 4^th larval instars ranged from 40 to 100 % and 32.5 to 92.5 % and reached 100 ,85 and 100 % for H. brunneipennis, respectively at the highest concentration after 7 days of treatment compared to 77.5 % and 60 % for S. littoralis and 95 and 85 % for H. brunneipennis treatments by Biofly. The DipelDf and W-Bus were highly efficient on the insect larvae, followed by Biofly and Protecto, respectively. Based on the LC₅₀ values, DipelDf was the highest toxic to S. littoralis and H. brunneipennis than that of the other compounds. Pupation and adults emergence percentages were reduced by all treatments compared to control.