Three isolates of Bacillus sphaericus were isolated from the rhizosphere of white rot free-onion plants. All isolates exhibited antagonistic potential against some fungi infecting peanuts. The highest antagonism to Fusarium so/ani was detected with isolate B1. Isolate B2 was the most antagonistic to Rhizoctonia solani , whereas Sclerollum rolfsii was most antagonized by isolate B4 . The three bacterial isolates were not significantly different with respect to antagonizing Macrophomina phaseolina. Application of these bacterial isolates ( 3 x 10 8 cfu/ml) to potted soil resulted in a 57-71 % reduction of damping-off in the greenhouse when used at a rate equivalent to 4 I //fed. Field application at the rate of 4.5 1/ fed. after sowing resulted in a 48-77 % reduction in peanut damping—off with a 22.7-54.54 increase in yield over the control treatment. The bio—control potentiality was slightly increased when the rate of application was raised to 6 I / fed. accompanied with 44-56 % increase in yield over the control treatment . Soil spray with B. sphacricus at the rate of 6 I / fed. after planting seed could be recommended.