Degradation of phenol in water was examined in a non-thermal plasma reactor combined with CeO2, Fe2O3/CeO2, and ZrO2/CeO2 catalysts. Plasma reactor was operated in a dielectric barrier discharge configuration, whereas, catalysts were characterized by XRD, BET, and Raman spectroscopy. The effect of applied voltage, phenol concentration and catalyst addition was studied. Typical results indicated that the degradation efficiency increases with increasing voltage, whereas, the best energy yield was obtained at lower applied voltage. Total organic carbon analyzer confirmed the mineralization of phenol, which was further enhanced by the catalyst addition up to 47.3%. The intermediate compounds formed during the plasma decomposition were identified by gas chromatography mass spectrometry (GC-MS). © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.