Abstract Water-distilled oils from the herbal parts of Origanum boissieri, endemic in Turkey, and Origanum bargyli were analyzed by GC/MS. Sixty-two and fifty-seven components were characterized representing 96% and 99% of the total components detected in the oils of O. boissieri and O. bargyli, respectively, with p-cymene (42.8% and 20.67%) and carvacrol (17.57% and 14.67%) as major constituents, respectively