Abstract The GC and GC/MS analysis of the essential oils from the aerial parts of Eupatorium adenophorum collected from different localities of Kumaun and Garhwal revealed the dominant presence of amorph-4-en-7-ol (5.8â17.7%), bornyl acetate (7.6â15.9%), p-cymene (0.1â16.6%), 3-acetoxyamorpha-4,7(11)-dien-8-one (0.3â16.3%), Î±-phellandrene (1.5â9.6%), camphene (â¶0.1â8.9%), Î±-bisabolol (1.7â7.8%), Î±-cadinol (0.6â6.2%) and amorph-4,7(11)-dien-8-one (3.2â5.7%). Amorphene derivatives (19.8â41.4%) may be considered as characteristic constituents of E. adenophorum. Key Word Index: Eupatorium adenophorum Asteraceaeessential oil compositionamorph-4-en-7-olamorph-4,7(11)-dien-8-one