Abstract: In recent years, antibiotic pollution has garnered widespread global attention. To explore green and energy-efficient treatment processes for antibiotic-contaminated wastewater, this study employed γ-FeOOH and CeO₂ to fabricate modified cathodes and investigated their performance in electric-Fenton (the Fenton reaction combining with electrochemical advanced oxidation processes) and bio-electric-Fenton systems (utilize the electrical energy generated by microorganisms to drive the electro-Fenton reaction) for the removal of conventional pollutants and sulfamethoxazole. The results demonstrated that the γ-FeOOH-modified electrode exhibited superior performance under a micro-electrochemical environment. At 900 mV, the removal rates of COD, TOC, and sulfamethoxazole reached 72.5%, 63.0%, and 91.6%, respectively. Notably, at 300 mV, the removal rates of COD and TOC by the γ-FeOOH-modified electrode exceeded those of the control group at 900 mV, indicating that the modified electrode could achieve efficient pollutant removal at a lower voltage, outperforming the traditional method of simply increasing the voltage and effectively saving electrical energy. In the bio-electric-Fenton system, the removal efficiency of the modified electrode for COD and TOC was significantly enhanced. The removal rates of COD and TOC by the γ-FeOOH-modified electrode increased by over 15 percentage points, while the removal rate of sulfamethoxazole was enhanced by more than 40 percentage points. By analyzing the degradation products of sulfamethoxazole, two potential pathways for its degradation were suggested. One was gradual mineralization to methane via 4-aminobenzenesulfonic acid as an intermediate, and the other was mineralization through nitrification and denitrification reactions. The research results can provide technical support for the development of efficient electrode materials, the utilization of biomicroelectronics and energy-efficient water treatment processes.