A dual chamber-microbial fuel cell (MFC) was used for simultaneous biotreatment of actual potato chips processing wastewater and electricity generation. The results demonstrated high removal efficiency of COD up to 90% after 14 days of continuous operation with 95.7 mW/m(2) power density at the closed circuit. An electrochemical model which describes the effect of various parameters on the performance of MFC was proposed to obtain the cell polarization. The results indicated the validity of the suggested model to create polarization curve with coefficients of determination (R-2) of 0.99, 0.92 and 0.92 for current, power densities, and voltage, respectively.