The aim of this work is the definition of a clean process for the treatment of landfill leachates by integration of efficient technologies, namely electrooxidation and selective ion exchange, that reduce the initial concentration of the pollutants and allow re-use of the treated water. Treatment of the leachates by electrochemical oxidation using a boron doped diamond electrode led to complete removal of chemical oxygen demand and ammonium nitrogen. However, as a result of ammonium oxidation the partial formation of nitrate was observed. Ion exchange removal of nitrate was experimentally analyzed using the selective resin Purolite A520 E obtaining satisfactory results.