The biological and toxicological effects of the formulations of three entomopathogenic fungi, Beauveria bassiana , Biovar, Paecilomyces fumosoroseus,  Apopka Strain 97and Metarhizium anisopliae, Bioranza, on house fly, Musca domestica L. were evaluated under laboratory conditions. Bioassays experiments were done to determine the effective concentration of fungi, which could be further formulated as a commercial biopesticide against domestic insects. The obtained results indicated that all tested fungi, applied at 1 % concentrations gave the lowest mortality percentages of house fly larvae ranging between 15 - 31.3 %. Metarhizium anisopliae 4 % gave the highest mortality percentages of house fly larvae (54 %). The lowest numbers of pupated larvae were recorded with the treatments of B. bassiana, P. fumosoroseus and M. anisopliae at 4 % concentrations. In addition, results indicated that there were significant differences in the numbers of emerged adults between all treatments and control, where the least numbers were recorded with the treatments of the tested fungi at 4 % concentration. The least percentages of emerged adults were recorded with the treatments of B. bassiana, P. fumosoroseus, and M. anisopliae at the treatments of 4 % concentration resulting 37.1, 38.5, and 35.7 %, respectively, in comparison with control treatment which resulted 90%.