(-)-Hopeanolin (1) was isolated from the acetone extract of the twigs of Shorea acuminata (Dipterocarpaceae), together with four resveratrol oligomers namely (-)-laevifonol, (-)-α-viniferin, (-)-vaticanol B and (-)-hopeaphenol. The structures of these compounds were established based on spectroscopic evidence, including UV, IR, NMR and mass spectra. Compound 1 showed the potent ability to protect -carotene bleaching by linoleic acid and also to scavenge DPPH radicals with IC50s 0.18 and 6.58 mM respectively. The presence of compound 1 and the other four resveratrol oligomers in this species have great chemotaxonomic significance on the relationship between Shorea and other genera of Dipterocarpaceae especially Hopea.