The antimicrobial activity of Hemidesmus indicus, Ficus bengalensis and Pterocarpus marsupium roxb was evaluated against pathogenic bacteria Stahylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumonia in an in vitro condition. Aqueous extracts from roots of H. indicus and barks of F. bengalensis and P. marspium roxb were tested for antimicrobial activity using the zone of inhibition method and also screened for phytochemicals. The aqueous extract of P. marsupium roxb inhibited growth of bacteria with the minimal inhibitory concentration ranging from 0.04 mg to 0.08 mg and extracts of F. bengalensis and H. indicus showed inhibition at the range of 0.04 mg to 0.1 mg against the bacteria tested. The susceptibility of bacterial pathogens was in the order of S. aureus, K. pneumoniae and P. aeruginosa. The antimicrobial activity of plant extracts was synergistic with antibiotics tested. Results of the present study suggest that the aqueous extracts of H. indicus, F. bengalensis and P. marspium roxb has significant antibacterial activity against pathogenic bacteria.