Antimicrobial activity of different extracts of bark of Moringa oleifera was studied against ten bacterial strains These bacteria are both gram +ve and gram -ve. Bark were extracted with a petroleum ether, chloroform, ethyl acetate, ethanol and aqueous . In the present work the antibacterial activity was done by cup plate method. The antibacterial activity was expressed as zone diameter in millimeters. Different extracts from bark of the plant was compared with standards like benzyl penicillin for gram +ve bacteria and streptomycin for gram –ve bacteria using DMF as control. The readymade media for inoculum and culture was obtained from Himedia labs. Prepared herbal extracts from the bark of the plant were screened against bacteria organisms at the concentration range between 50 µg and 300 µg/0.1ml. The present investigation reveals that the aqueous, chloroform and ethyl acetate extracts and in some cases petroleum ether extract showed significant antimicrobial activity when compared with standard.