abstract the chemical composition of the essential oils isolated by hydrodistillation from the flowers, leaves, stems and roots of tithonia diversifolia have been studied by gc-ms. the identified components accounted for 96.7 %, 93.7 %, 88.9 %and 93.7 % of the flower, leaves, stems and roots oils, respectively. the major constituents of flowers, leaves, stems and roots oils were -pinene (60.9 -75.7 %), -pinene (7.2-11.0 %) and limonene (0.9-4.3 %).