Lemon-scented gum (Eucalyptus citriodora Hook.) is an important aromatic tree species, cultivated in different parts of the world for the production of citronellal-rich essential oil from its leaves. In present study, essential oils derived from leaves, flowers and fruits of the plant were investigated and compared in detail using gas chromatography/flame ionization detector (GC/FID) and GC/mass spectrometry (GC/MS). Altogether, sixty-nine constituents, representing 92.9â97.5% of the total oil compositions were identified. Leaf oil was represented by citronellal (86.0%), as the chief constituent. Flower oil was dominated by citronellal (34.9%), α-pinene (22.0%), citronellol (11.9%) and β-pinene (4.6%), while the fruit oil contained α-pinene (40.7%), γ-terpinene (11.8%), citronellal (7.1%) and p-cymene (6.5%) as major components.