All plants containing active compounds are important. The beneficial medicinal effects of plant materials typically result from the combinations of secondary products present in the plant. In plants, these compounds are mostly secondary metabolites such as alkaloids, steroids, tannins, and phenol compounds, which are synthesized and deposited in specific parts or in all parts of the plant. Datura and Piper betle, medicinal plants were tested against three standard microorganisms E-coli DH5 (MTCC 2804), Bacillus amyloliquefaciens (MTCC 4012) and Pseudomonas aeruginosa (MTCC 1265) collected form MTCC Chandigarh for antibacterial activity. Among the medicinal plants tested in this study, Piper betle showed valuable antibacterial activities. The result showed that Piper betle didn’t show any antibacterial activity against Pseudomonas aeuroginosa whereas Datura stramonium didn’t show any antibacterial activity against Bacillus amyloliquefaciens and E-coli.