Smirnovia iranica Sabeti, is an adaptable plant of central sandy areas of Iran. This plant is very important because of many applications specially its application for grazing as a forage plant in sandy and dry lands of central Iran. The current research was carried out for the first one on determination of chemical components of oily compounds, extracted by n-hexane from Smirnovia iranica from Kashan, central Iran and antioxidant properties of polar methanol and non-polar n-heaxane extract of it. The results of GC-Ms analysis revealed 18 components with dodecanoic acid (10.83 %) and trans- β-ionone (10.04%) as the major components. Measuring antioxidant activity of the methanol and n-hexane extracts from S. iranica shows high activity in DPPH free radical scavenging and β-carotene bleaching assays for both extract. However methanol extract, exhibits stronger activities.