Abstract The oils obtained by steam distillation of the aerial parts and seed of Prangos ferulacea (L.) growing wild in Iran were investigated by a combination of GC and GC/MS. More than 30 compounds in the aerial parts oil, and about 20 compounds in the seed oil have been identified. The main constituents of the oil of the aerial parts were β-pinene (22.9%) and δ-3-carene (16.0%), whereas the seed oil comprised mainly β-pinene (33.0%) and α-pinene (10.1%) Key Word Index: Prangos ferulacea Umbelliferaeessential oil compositionα -pineneβ-pineneδ-3-carene