Advanced oxidation processes (AOPs) are widely used to degrade organic pollutants in aqueous solutions due to their ability to generate highly reactive radicals. However, the traditional Fenton reaction is limited by its required pH range of 2.8∼3.5 and the formation of Fe sludge. This study presents a hydroxyl radical filtrate containing highly active aluminum ions, prepared by filtering the reaction suspension of an Al+acid+H₂O₂ system. The filtrate effectively degraded oxytetracycline (OTC) in aqueous solution. The effects of Al dosage, reaction time, H₂O₂ concentration, and pH of filtrate preparation on oxytetracycline degradation efficiency were systematically investigated. Additionally, the mechanism underlying hydroxyl radical generation in the filtrate was analyzed.