<p>The cost-effective removal of chemical oxygen demand (COD) and ammonia nitrogen (NH₄⁺-N) from landfill leachate remains a significant challenge. In this study, a Fenton reaction was established using an iron-air fuel cell (IAFC), examining H₂O₂ yields with three types of air cathodes and two types of electrolytes. The removal performance and mechanisms of landfill leachate by the IAFC were also analyzed. The results demonstrated that the graphite (GR) cathode generated more H₂O₂ than the activated carbon (AC) or platinum-carbon black (PCB) cathodes. The GR cathode exhibited greater effectiveness in a 10 g/L Na₂SO₄ electrolyte. A 20 g/L NaCl electrolyte can efficiently enhance the power output of the IAFC. However, excessive Cl⁻ may react with Fe²⁺, inhibiting the Fenton reaction and leading to H₂O₂ accumulation. The IAFC achieved removal rates of 58% for COD and 19% for NH₄⁺-N in landfill leachate. Among these, 35% of COD was removed by adsorption, and 17% of NH₄⁺-N was removed by Fenton oxidation. Through Raman analysis, FeOOH and Fe₂O₃ formed in the reactor environment were identified as adsorbents for common pollutants in landfill leachate. Constructing a Fenton reaction using an IAFC not only effectively treats landfill leachate but also recovers electrical energy, aligning with principles of green and sustainable development.</p>