Abstract The content and chemical composition of the essential oil obtained from the leaves and inflorescences of Silphium integrifolium Michx. were studied. The oil content in the leaves and inflorescences was 0.27% and 0.31% v/w, respectively. Qualitative and quantitative analyses of distilled oils were made using GC and GC/MS. It was found that the oils had similar qualitative compositions but they differed quantitative. The main constituents in the leaf and inflorescence oils were Î±-pinene (9.8% and 14.0%), trans-verbenol (2.7% and 6.3%), bornyl acetate (2.2% and 7.0%), allo-aromadendr-9-ene (4.3% and 6.1%) and caryophyllene oxide (8.7% and 4.7%). Key Word Index: Silphium integrifolium Asteraceaeessential oil compositionÎ±-pinene