The essential oils which were obtained from the leaves, flowers and stems ofOcimum gratissimumin concentrations of 1.34%, 1.49% and 0.14% respectively, were examined by GC/MS. Fifteen constituents in the essential oil were identified with geraniol (83.7–88.8%) as the major constituent. Other major components included γ-muurolene (1.58–3.88%), β-caryophyllene (1.2–2.29%), neral (1.35–3.82%) and limonene (0.74–1.91%). Essential oil composition was similar among plant parts. Eugenol and thymol reported as the major constituent of Nigerian and Indian oil could not be detected in this oil. This is the first report of a geraniol-rich essential oil fromO. gratissimum.