Abstract The chemical composition of the essential oils obtained from the leaves of Eucalyptus camaldulensis Dehnh., E. citriodora Hook., E. dalrympleana Maiden, E. deanei Maiden, E. delegatensis R. Baker, E. globulus Labill, E. grandis W. Hill ex Maiden, E. nitens (Deane et Maiden) Maiden, E. saligna Smith, E. tereticornisSmith, E. urophylla S.T. Wake and E. vtminalis Labill, growing in Ethiopia were examined by capillary GC and GC/MS. The oil of E. camaldulensis was found to contain β-phellandrene (18.9%) and p-cymene (17.8%) while the oil of E. citriodora was rich in citronellal (73.3%) and citronellol (11.9%). E. dalrympleana oil contained α-pinene (26.2%), 1,8-cineole (19.3%) and α-terpineol (12.1%) and E. deanei oil contained 1,8-cineole (41.6%) and cryptone (17.6%); E. delegatensis oil contained α-pinene (28.3%), 1,8-cineole (26.4%) and γ-terpinene (18.0%), E. grandis oil contained α-pinene (44.7%) and β-pinene (30.5%) and E. saligna oil contained α-pinene (38.5%), β-phellandrene (12.2%) and 1,8-cineole (10.6%). Oils of the other Eucalyptus species contained α-pinene (13.2â44.7%) and 1,8-cineole (34.5â57.5%) as major constituents. Key Word Index: Eucalyptus camaldulensis Eucalyptus citriodora Eucalyptus dalrympleana Eucalyptus deanei Eucalyptus delegatensis Eucalyptus globulus Eucalyptus grandis Eucalyptus nitens Eucalyptus saligna Eucalyptus terelicornis Eucalyptus urophylla Eucalyptus viminalis Myrtaceaeessential oil compositionα-pineneβ-pinene1,8-cineoleβ-phellandrenep-cymenecryptoneα-terpineolcitronellalcitronellolγ-terpinene