A mesophilic bacterium was isolated from cow manure, and identified as Clostridium beijerinckii YA001 based on 16S rRNA gene sequence calculation using MEGA 5.0 and biochemical tests. This strain showed the ability to digest a wide range of carbon and nitrogen sources for hydrogen production, and it showed high hydrogen production performance using xylose as substrate. The optimum parameters for bio-hydrogen production in batch tests were pH 8.0, 1% substrate concentration, 40 degrees C and yeast extract as nitrogen source. The maximum hydrogen yield and the hydrogen production rate were obtained at 2.31 mol/mol xylose and 311.3 mL H-2/(Lh), respectively. These results indicate that C. beijerinckii YA001 is an ideal candidate for fermentative hydrogen production. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.