Genus Achillea millefolium L. (Asteraceae) consists of about 110-130 species. Nineteen species grow naturally in Iran of which seven are endemic. In this study, chemical composition of the essential oils of seven Achillea populations growing wild in northwest Iran, during the flowering period were investigated. The aerial parts were collected from Zonoz, Basmenj, Pirbala, Bonab, Shabestar, Kondlaj and Jolfa regions from Eest Azerbaijan province in May and June 2011. The essential oils were obtained by hydrodistillation method and analyzed by combination of GC-FID and GC-MS. Mean essential oil yield was calculate to be 0.1%, 0.4%, 0.1%, 0.2%, 0.1%, 0.25% and 0.4% (w/w) for Zonoz, Basmenj, Pirbala, Bonab, Shabestar, Kondlaj and Jolfa, respectively. Overall, 35, 38, 48, 43, 45, 37 and 42 compounds were identified from Zonoz, Basmenj, Pirbala, Bonab, Shabestar, Kondlaj and Jolfa, respectively. The main constituents of the oils were d-cadinol (23.3-3.7%), 1,8-cineole (18.5-7.7%), transnerolidole (2.6-11.3%), germacrene D (2.7-10.9%), alpha-pinene (1.06-9.44%), borneole (0.0-6.5%) and pinocarvone (2.8-6.3%). According to the obtained results, Basmenj and Zonoz are recommended as two suitable regions for the extraction of 1, 8-cineol and d-cadinol.