Abstract The essential oil hydrodistilled from herbal parts of Hippomarathrum boissieri (Umbelliferae), was analyzed by GC/MS. Eighty-nine compounds representing 92.4% of the oil were identified with Î²-caryophyllene (25.6%) and caryophyllene oxide (9.4%) and Î±-pinene (8.8%) as main constituents.