The oils of seven Achillea crithmifolia W. et K samples originated from two floristic regions in Bulgaria and raised under open field conditions were studied by GC and GC-MS. Among the forty assayed constituents, 1,8–cineole, artemisia alcohol, camphor and E-chrysanthenyl acetate were found to be the major components (concentration higher than 20.0%). The observed significant difference in the chemical composition of the oil samples, regardless their plant origin demonstrated the diversity of the studied plant species.