Abstract: With the development and utilization of vanadium and titanium resources, vanadium enters the surrounding soil and groundwater, which affects the ecological environment and poses a risk to human health, so it is important to find an environmentally friendly material for the treatment of vanadium-contaminated soil. Vanadium exists in the environment in divalent, trivalent, tetravalent and pentavalent states, with pentavalent and tetravalent states being the most common in nature, and the toxicity of vanadium depends on the valence state, with higher valence states being more toxic and migratory. Humic acid as a natural organic matter, exhibits a unique mechanism of electron transfer and microbial synergy during vanadium reduction. In order to investigate the power production in soil microbial fuel cell (SMFC) and its effect on vanadium migration and transformation in polluted soil, In this study, vanadium was used as a target pollutant, and Geobacter metallireducens was used as a test strain. Four treatment groups, namely, open circuit (OC), closed circuit (CC), humic acid (HA) or fulvic acid (FA), were set up and their electrochemical performance was determined. The four treatment groups of open circuit (OC), closed circuit (CC), humic acid (HA) or fulvic acid (FA) were added, and the electrochemical properties, soil physicochemical properties, and changes in the organic matter fractions were determined, focusing on the transport and transformation of vanadium heavy metals in the soil. The results showed that the electrochemical performance and the cathodic enrichment rate of vanadium increased in SMFC-CC, SMFC-HA and SMFC-FA compared with SMFC-OC, among which SMFC-FA operated the best, with its output voltage stabilized at about 669.32 mV and the maximum power density of 40.08 mW/m². Vanadium in SMFC was mainly realized to the cathode under the effect of electromigration. The cathode migration of vanadium in the soil was gradually transformed into a more stable residual state after remediation by SMFC, in which the addition of fulvic acid increased the vanadium in the residual state from 38% to 54%. Comparative analysis of the changes in vanadium concentration in the cathode and anode regions in the SMFC reveals that vanadium is ultimately enriched in the cathode region, and the enrichment rate of vanadium in the cathode region is positively correlated with the electrochemical performance of the SMFC. V⁵⁺ in the soil was reduced to V⁴⁺ by microorganisms and electric field, migrated behind the cathode and enriched, with the enrichment rate reaching 28.17% in the fulvic acid group.SEM was used to observe the microscopic morphology of the anodic biofilm, FTIR to analyze the changes in the functional groups of soil humic acids, and three-dimensional fluorescence spectroscopy to resolve the electron shuttling substances and extracellular polymers in SMFC.Comparing the strengthening effects of fulvic acid and humic acid, the fulvic acid system demonstrated superior restorative potential. In addition, the presence of fulvic acid led to an increase in the number of electroactive bacteria, the concentration of organic matter and extracellular polymers, which was more favorable for vanadium migration and transformation. In conclusion, this study revealed the mechanism of humic acid-enhanced microbial fuel cells and provided a theoretical basis for the application of bioelectrochemical technology in the remediation of vanadium-contaminated soil.