Sugarcane bagasse is a large by-product discarded in sugarcane processing factories. In this research, sugarcane bagasse was used to prepare highly valued trans-ferulic acid by alkaline-hydrolysis and purification through combination of activated charcoal adsorption and anion macroporous resin exchange chromatography. The results showed that powdered activated charcoal had much higher adsorption capacity for ferulic acid than that of granular activated charcoal and adsorbed ferulic acid at very low concentration; the adsorbed ferulic acid could be totally washed out by 0.2 mol/l NaOH but only a small part by ethanol or acetic ether. These properties made it possible to remove other substances produced by alkaline-hydrolysis through washing out using hot water and acetic ether before desorbing ferulic acid from active charcoal by NaOH. High purity of ferulic acid was obtained by further treatment of anion macroporous resin exchange chromatography after its washout from the activated charcoal. (c) 2006 Elsevier Ltd. All rights reserved.