It is judicious to be reminiscent of the environmental conditions of plant growth being a primary factor affecting the components and amount of constituents in essential oils making the pharmacological action of essential oils uncertain. The wide range of distribution for Vitex agnus castus (VAC) in Iran made it a suitable candidate for assessing the chemical profiles of samples collected from three different places. The GC-MS analysis of the essential oils obtained by the hydrodistillation of the plant materials, led to identification and quantification of 30, 7, and 18 compounds representing 74.95, 82.53 and 84.41 percent of total oil for Qum, Khorasan and Tehran samples, respectively. All samples were rich in monoterpenes including monoterpene hydrocarbons (42.84-64.48%), monoterpene alcohols (~0.7-8%) and sesquiterpenes (9.45-31.33%). A diterpene compound (3.11%) was found only in Tehran samples. The variations in presence or absence and also the identity of some compounds were quite evident in the VAC fruits.
