Microbial resistance to conventional antibiotics is a global problem. The use of medicinal plants as alternative to conventional antibiotics needs scientific basis to prove their efficacy. This work investigates the efficacy of extracts of Moringa oleifera as an antimicrobial agent against Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella sp and Staphylococcus aureus. An inhibition by M. oleifera leaf extracts was noticed against all the tested bacteria except P. aeruginosa. Phytochemical analysis indicated the presence of tannins, flavonoids, terpenoids and saponins in all the plant extracts. Ethanol extracts of M. oleifera revealed the presence of flavonoids, tannins, alkaloids and saponins. Flavonoids and saponins were also observed in the methanol extract of the plant while only phenols and glycosides were absent in aqueous extract. Minimum Inhibitory Concentration (MIC) range of 7.34mg ml-1 to 29.37 mg ml-1 was noticed with the minimum value observed for S. aureus. The study reveals that M. oleifera showed high degree of inhibition against all the bacterial strains.