The antibacterial effect of Ocium extracted from aromatic plant was investigated against listeria monosytogenes. Agar well diffusion and tube dilution methods were used and the data recorded demonstrated antibacterial activity of essential oil against the test bacteria. The bacteria was grown at 37c in a chemically defined medium were more sensitive to essential oil concentration of 50, 62 ,5 and 100μg/ml in relation, to those cultivated in complex medium at 37c. The agar well diffusion was also evaluated. The results yield a zone of inhibition of 25mm. These established a good support to the use of this plant in herbal medicine and as base for the development of new drugs and phytomedicine.