Abstract The essential oils obtained from two populations of Lavandula dentata L. from Algeria were examined by GC, GC/MS and 13C-NMR. The oils were rich in β-pinene (6.0â26.0%) and 1,8-cineole (0.9â36.3%). The two oils exhibited different compositions: cineole/β-pinene and β-pinene/trans-pinocarveol. Despite some variations of the contents of the main components, the plant produced oil belonging to the same chemotype throughout its life cycle. Key Word Index: Lavandula dentata Lamiaceaeessential oil compositionβ-pinene1,8-cineolechemical variability