The essential oil composition of ten accessions of Origanum vulgare L. ssp. vulgare collected from wild populations of the sub-temperate region of the Central Himalayas and subsequently grown under identical climatic conditions in Uttrakhand state of India were analyzed by gas chromatography (GC) and GC/mass spectrometry (GC/MS). A total of forty-six components representing 92.6â99.8% of the total oil were identified in essential oils isolated from seven different locations. The major constituents of the essential oils were phenolic compounds (13.7â90.5%), represented mainly by thymol (13.7â85.9%) and carvacrol (1.5â63.0%). Two chemotypes were identified: the first, with a prevalence of thymol (IC589087, 85.9%; IC589085, 85.0%) and the second, characterized by the prevalence of carvacrol (IC589079, 63.0%). Results indicated that accessions collected from higher altitude (>3200 m) possessed high thymol content (>85%). This chemical study attempts to provide an insight on the relationship between chemical composition of essential oil and chemotypes in O. vulgare L.