The hydrodistilled essential oils from the leaves, stem, wood and roots of a Cinnamomum sp., obtained from wild stands in the Hà Bac province of Vietnam, were examined by a combination of high resolution GC and GC/MS. 2-Methylene-3-buten-1-yl benzoate, a hitherto unknown plant component, was found to be the major constituent of the leaf (85.9%), stem (92.4%) and wood (44.2%) oils. Camphor was the second most abundant constituent of the wood oil (13.0%). The root oil contained mainly safrole (63.8%) and camphor (17.9%). The structure of 2-methylene-3-buten-1-yl benzoate was elucidated by mass, 1H- and 13C-NMR spectrometry. Spectral data are presented.