In a novel bio-electrochemical system (BES) for hydrogen and electricity co-production with acetate substrate, the anolyte pH and cathode Pt loading effects are investigated to improve the cell performance for hydrogen and electricity co-production and reduce the cost. The optimized anolyte pH is 9. The maximum hydrogen production rate of 0.55 m(3) m(-3) d(-1) and COD removal of 76% are obtained under optimal anolyte pH in the present BES. Over high or over low anolyte pH decreases the hydrogen production rate and COD removal. In addition, the experiments show that there is no considerable difference for the power density output and steady state current when the Pt catalyst loading is above 0.1 mg cm(-2). But when the Pt catalyst loading is lower than 0.1 mg cm(-2), the power density output and current decreases significantly. About 1.7 W m(-3) power density output can be obtained by using 0.1 mg cm(-2) Pt catalyst in the present research. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.