Abstract: To address the environmental pollution caused by the novel herbicide metamifop, a dual-chamber microbial fuel cell （MFC） was constructed to investigate the effects of different operating conditions on its performance in degrading this herbicide and generating electricity, and its electron transfer process and degradation mechanism were explored.The results showed that the optimal electricity-producing bacterial strain was Desulfovibrio desulfuricans, achieving a metamifop degradation rate of 78.3% and a power density of 103 mW·m⁻². The optimal initial pH was 8.0, under which the degradation rate was 81.5%. Within the tested concentration range, the MFC performed best at an initial metamifop concentration of 0.1 mg·L⁻¹, while high concentrations of the pollutant exerted an inhibitory effect. Exogenous addition of an electron shuttle （riboflavin） significantly enhanced MFC performance, with 20 mg·L⁻¹ riboflavin increasing the degradation rate to 94.5% and the maximum power density to 175 mW·m⁻², while also increasing the intracellular NAD⁺/NADH ratio and NADH dehydrogenase activity. It was also found that electron transfer inhibitors （rotenone and capsaicin） suppressed MFC performance. Multiple degradation intermediates were identified through Liquid Chromatography-Mass Spectrometry （LC-MS） analysis, and possible degradation pathways for metamifop were proposed. The findings provide a reference for the application of microbial fuel cells in the field of pesticide pollution remediation.