There is a growing body of antibiotics which are accumulated after usage by humans and animals for health reasons in the environment. Here, a 3D CeO2/RGO composite was obtained by using hydrothermal self-assembly synthesis method and in-situ deposition method. 3D CeO2/RGO composite was used firstly as cathode for efficient degradation of antimicrobial agent ciprofloxacin (CIP) in electro-Fenton system. The obtained composite was characterized by XRD, SEM, BET, TEM, HPLC-MS, CV and EIS. Synergistic effects from the electrosorption property of CIP on 3D CeO2/RGO and the electrocatalytic activity of CeO2 and the strong oxidizing property of hydroxyl radical (center dot OH) from electro-generated H2O2 in situ promote to reach about 100% efficient degradation of CIP. With the hydrothermal reaction time of 8 h and a current of 400 mA, about 100% antibiotics can be cleaned, and 91% TOC can be removed after 6.5 hat the experiment condition of pH = 3 and 0.1 mmol.L-1 Fe2+ in 0.05 mot.L-1 Na2SO4 solution. 3D CeO2/RGO composite can be used effectively as cathode in the electro-Fenton treatment for the deep degradation of CIP. (C) 2016 Elsevier B.V. All rights reserved.