Abstract Water-distilled essential oils from the aerial parts of Teucrium pestalozzae, T. sandrasicum and T. montanum were analyzed by GC/MS. The major constituents characterized in the oils were as follows: T. pestalozzae (endemic in Turkey) contained β-caryophyllene (27.6%) and germacrene D (13.8%); T. sandrasicum (endemic in Turkey) contained germacrene D (27.9%), β-caryophyllene (9.1%) and sabinene (8.9%) and T. montanum contained sabinene (11.3%), δ-cadinene (6.3%), germacrene D (5.8%), α-copaene (5.7%), (E)-β-farnesene (5.5%) and α-pinene (5.2%).