In this study, from a eutrophic lake we enriched and separated photosynthetic bacteria, which can consume sewage as well as initiate extracellular electron transfer and thereby produce electricity. We isolated and purified photosynthetic bacteria from improved enriched media and isolated media and identified them using morphological and molecular methods. We used the national standard method and spectrophotometry to determine the chemical oxygen demand, total nitrogen, and total phosphate. To detect the electricity production of the photosynthetic bacteria, we used an electrochemical workstation. Our results show that the photosynthetic bacteria strain DH-3 has high similarity with Rhodobacter sphaeroides. We found the removal rates of COD, TN, and TP to decrease in the wastewater medium. The electrochemical workstation detected that strain DH-3 produced maximum electricity at 7.5 mA/m,2, and maximum power at 0.056 W/m,2,. Our results indicate that strain DH-3 has potential application in future wastewater treatment and resource recovery technologies.