Liverwort Plagiochasma intermedium was screened for its active metabolites using standard phytochemical tests. Different concentrations of  its aqueous  extract were subjected to antimicrobial activity assay using plant pathogenic bacterium Pseudomonas syringae as test organism, in the presence of the positive control drugs streptomycin and amoxicillin.  Inhibition of bacterial growth was measured in terms of number of colonies and diameter of inhibition zone appeared after 24 hours of incubation at 35 ± 2°C. Results showed that all the concentrations of extract were active in inhibiting bacterial growth. Lower extract concentrations were less effective but higher concentrations showed pronounced effect to check bacterial growth. Among all concentrations 100 per cent extract concentration was found to be most potent.