Essential oil vapors obtained by the hydrodistillation of Prangos ferulacea (Umbelliferae) were tested on the different stages of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) and egg parasitoid Trichogramma embryophagum Hartig (Hymenoptera: Trichogrammatidae). Extracts of the volatile fractions from P. ferulacea were analyzed by capillary gas chromatography-mass spectrometry. The major compound of the essential oil was detected as 2,3,6-trimethyl benzaldehyde (66.59%) and the minor compound was heneicosane (0.02%). The third instar larvae of E. kuehniella (LC50 : 379.662 mu L L-1 air and LC99 : 538.755 mu L L-1 air) and the pupal stage of T. embryophagum (LC50 : 5.947 mu L L-1 air and LC99 : 19.568 mu L L-1 air) were found to be the most tolerant stages. The essential oil was toxic to the adult stages of both the pest and its parasitoid with 100% mortality obtained after 24 h at 1.0 and 0.25 mu L L-1 air, respectively. The LC50 and LC99 values of the essential oil against the egg stages of E. kuehniella and T. embryophagum were 320.372-486.839 mu L L-1 air and 2.121-5.662 mu L L-1 air, respectively. In general, the mortality rate increased with the increasing concentration of essential oil. The results of the study indicated that essential oil of P. ferulacea should be used as a control agent against E. kuehniella for an integrated pest management program.