The essential oil from fresh leaves of Croton ovalifolius Vahl was obtained by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). Twenty-eight compounds, which represent 90.4% of the total constituents of the oil, were identified. The most abundant constituents were β-caryophyllene (20.8%), bicyclogermacrene (12.1%), germacrene B (10.7%),τ-cadinol (8.1%), spathulenol (6.0%) and caryophyllene oxide (5.2%). Copyright © 2000 John Wiley & Sons, Ltd.