A novel immobilized solid acid coating on Q235 carbon steel was successfully prepared via plasma electrolytic oxidation. Sulfate functionalized Fe3O4/FeAl2O4 was confirmed by XRD, TEM and XPS analysis and surface acidic property was verified by NH3-TPD measurement. Fenton-like degradation performance was evaluated by employing phenol as target pollutant. Fast phenol degradation under the wide range of pH (pH 6–9) was accomplished within only 11min. Without sulfate functionalization, phenol could hardly be degraded by Fenton-like oxidation which meant that after sulfate functionalization the existence of acidic microenvironment on the catalyst surface not only provided an optimal circumstance for enhanced Fenton-like reaction, but also avoided adjusting pH of the treated wastewater. A reasonable Fenton-like degradation mechanism was proposed. This paper offered a novel design thought for synthesizing excellent Fenton-like coating catalyst under circumneutral pH.