Abstract: The aim of the study was to analyze and compare the chemical constituents of essential oils extracted from the leaves of E.grandis×E.urophylla by two kinds of methods,and to provide basis for the further research and more application of Eucalyptus resources.GC/MS was used to analyze and compare the extraction rate and chemical constituents of essential oils extracted from the leaves of E.grandis×E.urophylla by steam distillation(SD) and supercritical CO₂ extraction process(SFE-CO₂).By the way of SD and SFE-CO₂ extraction,the extraction rate of essential oil were 0.61% and 7.8% respectively 55 constituents were identified,which accounted for about 98.18% of the total essential oil by SD.While 29 constituents were identified,which accounted for about 99.59% of the total essential oil by SFE-CO₂ extraction.The contents and effective constituents(such as α~Pinene and Cineole) of essential oils by SFE-CO₂ extraction were higher than that by SD.The SFE-CO₂ extraction was more favorable to the industrial production.