The typical electro-Fenton process requires electricity to produce H2O2 electrochemically on the cathode for generating powerful oxidants (e.g., hydroxyl radical) to degrade persistent organic pollutants. A new bioelectro-Fenton system in a two-chamber microbial fuel cell (MFC) was proposed using a Fe@Fe2O3/carbon felt composite cathode for simultaneous oxidation of wastewater at the anode and cathodic degradation of biorefractory pollutant by Fenton's reaction. Under the short-circuit conditions, it was found that the rate of Rhodamine B (RhB) decolorization, TOC removal and stoichiometric efficiency was significantly improved as compared with that found under close-circuit conditions (1000 Omega). The enhancement was determined to be caused by an increase in cathodic current density that was favorable for H2O2 production. (C) 2010 Elsevier B.V. All rights reserved.