Abstract The essential oil composition from the aerial parts of Pimpinella barbata (DC.) Boiss. (Apiaceae) at full-flowering stage from Iran was studied by GC and GC/MS. A total of 32 compounds have been identifed, accounting for 97.0% of the total oil. Analysis of the oil showed that the oil of P. barbata was rich in a phenylpropanoid fraction, in which methyl eugenol (34.0%) and elemicin (6.9%) were the two main constituents. The main compouds of monoterpene fraction were limonene (26.6%), sabinene (6.7%) and perillaldehyde (5.2%). Key Word Index: Pimpinella barbata Apiaceaeessential oil compositionmethyl eugenollimonene