Higher plants have been shown to be a potential source for the new anti-microbial agents. Essential oils are becoming increasingly popular as naturally occurring antimicrobial agents. The present study was designated to determine the chemical composition and to evaluate the antimicrobial properties of Ehinophora platyloba DC. essential oil. The plant was collected from central region of Iran. Hydrodistillation was used to isolate the essential oil and the chemical analysis was performed by gas chromatography which was coupled to a mass spectrometer. The antimicrobial activity of the oil was determined against selected microorganisms, using a disc agar diffusion method. Ciprofloxacin, ketoconazole and amphotericin B were used as a reference for inhibition zone diameter. The GC / MS analysis showed that the major constituents of the oil were monoterpene hydrocarbons and an alcoholic monoterpene, but the concentrations of these compounds varied extensively through the examined oil. The results of the antimicrobial assay show that essential oil of Echinophora platyloba DC. posses significant antimicrobial effects against 8 studied microorganisms. The essential oil obtained from E. platyloba has an antimicrobial activity comparable to the one observed in other Echinophora species. These effects relate to antimicrobial activity of components of essential oil and possibly synergistic relationship between them.