In this study, antibacterial activity of ethanol extract and essential oil of 10 Iranian folklore herbs including, Heracleum  lasiopetalum Boiss., Satureja bachtiarica Bunge., Thymus daenensis Celak., Ziziphora teniur L., Echiophora platyloba L., Dracocephalum multicaule Benth., Kelussia odoratissima Mozff., Mentha longifolia Hudson., Achillea  kellalensis Boiss. and Stachys lavandulifolia Vahl. were investigated against of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae by agar disc diffusion and serial dilution assays. Most of the extracts and essential oils showed relatively high antibacterial activity against all the tested bacteria with the diameter of inhibition zone ranging between 8 and 23 mm. Of the plants studied, the most active extracts were those obtained from essential oil of Satureja bachtiarica and Thymus daenensis. The MIC values for active extract and essential oil ranging between 0.039 and 10 mg/ml. The results obtained appeared to confirm the antibacterial potential of the plants investigated. In conclusion it can be sa...