In this experiment, a new bimetal low–cost Cu–Sn alloy was synthesized and it was tested as catalyst for oxygen reduction reaction (ORR) in MFC and the results were compared with the commercially available Pt-C catalyst. Cyclic voltammetry for evaluating ORR of the test cathode containing Cu-Sn catalysts under oxygen saturated environment displayed large ORR current peak, showing less overpotential demand for ORR. Maximum power density of 457 mW/m2 obtained from MFC using Cu–Sn catalyst, was found to be slightly higher than the power density of 446 mW/m2 demonstrated by MFC using Pt based cathode. Biochemical conversion of organic matter to direct electric current in Cu–Sn based MFC occurred at a coulombic efficiency of 55.8%, while demonstrating 92% of chemical oxygen demand removal. This study demonstrated application of low cost Cu–Sn bimetal alloy as excellent ORR catalyst in MFC and would be very helpful to commission larger MFCs for field applications to harvest energy in the form of direct electricity from wastewaters while offering wastewater treatment.