Plant based traditional medicine plays an essential role in human and animal medication and a significant number of world population rely on traditional medicines for their primary health care. However, scientific evaluation and confirmation of traditionally used medicinal plants is scarce. Thus, the present study was aimed to evaluate the antibacterial activity of four medicinal plants namely Buddleja polystachya, Osyris quadripartita, Clausena anisata and Premna schimperi against pathogenic bacteria Staphylococcus aurous, Staphylococcus epidermises, Escherichia coli and Klebsiella pneumonia. The selected medicinal plants were collected from the field and the bioactive ingredients of plant leaf samples were extracted using maceration method. The antibacterial activity of leaf extracts was evaluated by disc diffusion method. The minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC) were determined by agar dilution method. The phytochemical analysis revealed the presence of alkaloid, flavonoid, phenolic compounds, saponins, tanins and terpenoids. The extracts of each species showed antibacterial activity and there is significance difference among medicinal plant extracts. The extracts of Buddleja polystachya exhibited the highest antibacterial activity at 100mg/ml followed by Osyris quadripartita against all the tested bacteria. The MIC and MBC values ranged from 25-100mg/ml. Buddleja polystachya and Osyris quadripartita showed the lowest MIC and MBC values against Klebsiella pneumonia. The medicinal plant Buddleja polystachya was more potent against each human pathogen. It is recommended that further research in a similar manner be done on and unexplored parts of the studied plants.