Abstract: A microbial fuel cell system was built by using the mixed solution of K₃Fe (CN)₆ and NaCl as catholyte, acclimated sediment of an artificial lake as the source of microbial species, and streptomycin wastewater as anolyte; the effect of co-substrate addition on the purification effect and electricity generation ability of the microbial fuel cell was investigated. The results show that the electricity generation ability and wastewater treatment effect of microbial fuel cell with streptomycin wastewater as anolyte are quite poor and deteriorate even further with the increase of the streptomycin concentration. However, the electricity generation ability and wastewater treatment effect of the microbial fuel cell can be significantly improved by adding glucose as a co-substrate to the anode streptomycin wastewater. In case without the co-substrate, the COD removal rate is only 52% when the concentration of streptomycin is 50 mg/L, with a steady electric current density of 25 mA/m² and a steady output voltage of 4.72 mV; by adding the co-substrate, the COD removal rate reaches 92%, with a steady electric current density of 300 mA/m² and a steady output voltage of 54 mV.