Abstract: Microbial fuel cells (MFCs) technology is a new type of wastewater treatment and energy recovery technology combining wastewater treatment with energy recovery. However, due to the limitations of the irreversible reaction processes on the cathode and anode, the losses of electricity caused by the activation loss and ohmic loss make it difficult to obtain a high and stable energy output, which restricts the further development of MFCs. With the technological progress in materials and biology in recent years, the above losses can be reduced by reasonable design. Aiming at the two main components of reducing internal resistance, i.e. activation internal resistance and ohmic internal resistance, the recent technological advances in the improvement of electricity generation performance of MFCs were systematically summarized, including the screening of electricity-producing bacteria, the explanation of electron transfer mechanism, the innovation of electrode materials and functional modification methods, the advancement of partition materials and the optimization of reactor configuration. Finally, the technical development for reducing internal resistance of MFCs in the future was prospected.