AbstractWater‐distilled essential oil of leaves and flowers of Tanacetum argyrophyllum (C. Koch) Tvzel. var. argyrophyllum and leaves of Tanacetum argenteum (Lam.) Willd. subsp. canum (C. Koch) Grierson var. canum, herbal parts of Tanacetum praeteritum (Horwood) Heywood subsp. praeteritum and Tanacetum praeteritum (Horwood) Heywood subsp. massicyticum Heywood (Compositae), endemic taxa, were analysed by GC–MS. Sixty‐eight, 51, 50, 47 and 72 compounds, representing 90%, 86%, 72%, 91%, 83% of the oils, respectively, were identified. α‐Thujone (52% and 63%) was the major constituent of Tanacetum argyrophyllum var. argyrophyllum leaf and flower oils, respectively. Caryophyllene oxide (13%) and α‐thujone (12%) were found as the main constituents of the oil of Tanacetum argenteum subsp. canum var. canum. Borneol (28%), 1,8‐cineole (12%) and bornyl acetate (10%) were the major constituents of T. praeteritum subsp. praeteritum. In the oil of subsp. massicyticum, α‐thujone (51%) and β‐thujone (10%) were characterized as the main constituents. Copyright © 2001 John Wiley & Sons, Ltd.