The chemical composition of the essential oil from flowering aerial parts of Pulicaria dysenterica (L.) Bernh (Asteraceae), growing wild in Iran, was determined by GC and GC-MS. Nineteen compounds, representing about 96.0 % of the oil, were identified. Oxygenated sesquiterpenes (43.5 %) and sesquiterpene hydrocarbons (41.5 %) were found to be the major fraction of the oil. Also ar-curcumene (28.3 %), epi-α-cadinol (16.4 %) and (E)-coniferyl alcohol (11.0 %) were the main components of the oil.