The chemical composition and antioxidant activity of the essential oil from the stems of Bursera graveolens (Kunth) Triana et Planch grown in Manabí (Ecuador) were studied. Ninety-nine compounds were identified in the essential oil. Monoterpene hydrocarbons and oxygenated monoterpenes were the most represented classes of volatiles with 35.4% and 30.4%, respectively. The main constituents of the oil were limonene (34.9%) and α-terpineol (13.4%). Antioxidant activity were examined using 1,1-diphenyl-2-picryl-hydrazyl assay and the ferric-reducing antioxidant power assays. The essential oil had a moderate scavenging effect and it showed ferric reducing activity. These results validate the use of this plant in the traditional medicine.