From the 6 Indian medicinal plants belongs to 3 botanical families were selected on the basis of their use in the treatment of infectious diseases. Hexane and ethanol extracts of the plants were studied for their antimicrobial activity against various human pathogenic organism against Gram -positive bacteria S. aureus, S. epidermitis, B. subtilis, B. cereus, M. luteus, and Gram -negative E. coli, P. aeruginosa and fungi C. albicans, A. niger was studied by disc diffusion method. The extracts of S. fruticosa, T.asiatica, T. ciliata showed marked antimicrobial activity. It is significant to note that though the plant extracts showed activity against P. aeruginosa they had no activity against the other Gram - negative bacteria E. coli. Concentration tested was 5 μl of the plant extracts (250 μg /disc) in each sterile filter paper disc (diameter, 6 mm).