Abstract The essential oil of Hyptis floribunda Briq. ex. Micheli collected from Oran, Argentina (Yungas area) was analyzed by GC and GC/MS. In the oil, 17 compounds were identified. The oil was found to be rich in sesquiterpene hydrocarbons (74.6%), the most abundant being bicyclogennacrene (37.8%), γ-cadinene (17.9%) and δ-cadinene (10.7%). Elemol (11.4%) was the major oxygenated sesquiterpene. Key Word Index: Hyptis floribunda Lamiaceaeessential oil compositionbicyclogermacreneγ-cadineneδ-cadineneelemol