The stem and leaf oils of Eupatorium coelestinum L., Compositae, were analyzed by a combination of high resolution GC, GC/MS and 13C-NMR. More than 30 components were identified, representing 75-77% of the oils. The principal oil constituents were methyl chavicol (9.7-45.2%), hornyl acetate (6.2-12.6%), camphene (0.3-11. 9%) and cis-cadin-4-en-7 -01 (5.2- 10 .9%) in the stem and leaf oils, respectively. The oils contained about 500Al of oxygenated compounds, which contributed to the special odor of these oils.