The lethal effect of Beauveriabassiana isolateon whitefly Bemisia tabaci revealed that the least percentage of adult mortality was 11%, which was recorded with the lowest tested concentration (1X10³ spores/ml), while the highest percentage of adult mortality (56%) was achieved at 1X10⁷ spores/ml, compared with 5% in natural mortality. In a similar trial to evaluate the effect ofB. bassiana against the aphid lion Chrysopela carnea (Stephens), exposure of the2^ndlarval instar of aphid lion to B. bassianaisolate,either through direct or indirect exposure, resulted in adverse effects on the total percent of larval mortality, which was concentration dependent. Whereas the total larval death recorded 3% in control trials, data in case of direct exposure revealed 9 to 41% of larval death at 1X10³and 1X10⁷ spores/ml, respectively. Comparable trend was recorded with larvae indirectly exposed. Increase in larval mortality was recorded by 5 to 15%. Therefore, care is needed when using these fungal isolates in the case of using larval predator aphid lion in the programs of integrated control.