In the present study essential oil of three herbs (Sonchus asper, Tephrosia purpurea and Leucas indica) was extracted and characterized by Gas chromatography. Characterization results showed the presence of several antimicrobial components in the essential oil of Sonchus asper such as dibutyl phthalate which is well known for its antibacterial efficacy. Antimicrobial efficacies of extracted essential oils were evaluated against five different pathogens i.e. Pseudomonas aeruginosa MTCC 2474, Staphylococcus aureus MTCC 1144, Escherichia coli MTCC 40, Klebsiella pneumoniae MTCC 4030 and Streptococcus pyogenes MTCC 442. The essential oil of Sonchus asper gave maximum zone of inhibition against Staphylococcus aureus MTCC 1144 which is known to be the main causal organism of wound infection whereas Tephrosia purpurea and Leucas indica showed the least efficacy against all the test organisms.