Abstract: Vitex pseudo-negundo (Hausskn.) is a perennial plant of Lamiaceae family which
grows naturally in the vicinity of seasonal rivers of Iran. The present study was aimed to characterize
the essential oils composition of five Iranian populations of V. pseudo-negundo. The aerial parts of
the plant were collected at flowering stage. GC-FID and GC-MS analyses of the essential oils identified
a total of forty-one components in the examined essential oils, accounting for 95.8- 98.5 % of the total
composition. According to the results, no significant differences was observed among the main
compositions of the essential oils. In all investigated populations, the main fraction was represented by
monoterpene hydrocarbons with α-pinene (25.3-29.2 %) and limonene (7.89-9.85 %) as the most
abundant components. (E)-β-methyl ionone (12.38-17.37 %), (E)-β-caryophyllene (3.7-9.8 %) and β-
eudesmol (5.0-6.1 %) were the other main components of the essential oils.