A novel biomass-synthesized Au-SrTiO3 composite was prepared by syzygium extract and used for H-2 evolution from formaldehyde aqueous solution without any additives at low temperature. The as-prepared catalyst exhibits the best performance for H-2 evolution (111.15 mu mol g(-1)) compared with the glucose-Au-SrTiO3 and UV-Au-SrTiO3. Through Xray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectra (FTIR), and X-ray photoelectron spectroscopy (XPS), it was found that the high activity of the syzygium-Au-SrTiO3 catalyst could be linked to the interaction between hydroxyls from biomass and the Au-SrTiO3 which resulted in the Au(I)/Au species. Also, the oxygen vacancies and organic biomass groups on the support may play an important role in the activation of formaldehyde, which was further transformed into formate intermediates and decomposed into hydrogen and carbon dioxide. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.