The hydrodistilled essential oils of fruits and umbels of Prangos ferulaceae (L.) Lindl growing in Iran were analysed by gas chromatograph-mass spectrometer. Six compounds, comprising 93.7 and 94.7% of the total fruits and umbels oils, were identified, respectively. alpha-Pinene and cis-ocimene are the major components of the oils. The essential oils show high antibacterial effect against Bacillus cereus.