Biologically catalyzed electrochemical treatment of real field dairy wastewater in association with power generation was studied in single chamber non-catalyzed microbial fuel cell (MFC, open-air cathode). The performance was evaluated at four organic loads employing anaerobic mixed consortia as anodic biocatalyst. Experimental data illustrated the integrated function of MFC to harness bioelectricity from the treatment of dairy wastewater. Along with good substrate degradation (chemical oxygen demand (COD), 95.49%), MFC also documented good removal of proteins (78.07%), carbohydrates (91.98%) and turbidity (99.02%). A steady increase in MFC performance was observed with increase in substrate load. Maximum volumetric power production (1.10W/m3; 308mV; 1.78mA) was observed at 4.44kgCOD/m3. MFC performance as power generator was characterized based on polarization behavior, cell potentials, cyclic voltammetric analysis and sustainable power estimation. In view of inherent advantages of the process, if optimized and understood well, this integrated approach can be a good replacement for the conventional biological and electrochemical wastewater treatment processes. © 2010 Elsevier B.V.