BACKGROUND: To make the treatment of seafood wastewater more economical and sustainable, this study aims to examine electricity generation and simultaneous degradation of organic substances from seafood wastewater in single-chamber (SC) and dual-chamber (DC) microbial fuel cell (MFC). RESULTS: By supplying the MFCs with seafood wastewater, the maximum power density produced from the SCMFC was higher than that produced from the DCMFC, which is a consequence of the difference in internal resistance of the two systems. The electrochemical reduction of oxygen catalyzed by C/CoTMPP was comparable with that promoted by commercial C/Pt catalyst. The SCMFC achieved higher organic degradation than the DCMFC, which corresponded to less accumulation of volatile fatty acids being decomposed aerobically promoted by the oxygen diffused from the cathode in the absence of the membrane. Owing to electron losses via aerobic decomposition rather than the electricity-producing pathway, the higher removal efficiency was in line with the low coulombic efficiency. In addition, the DCMFC having a membrane had a more severe pH polarization than the SCMFC without the membrane. CONCLUSIONS: This study provides a conceptual demonstration of sustainable utilization of seafood wastewater while carrying out biological decomposition in an MFC system in an economical manner. Copyright (C) 2012 Society of Chemical Industry