[en] Highlights: • CeO₂/MWCNTs composites were synthesized by a hydrothermal method. • CeO₂/MWCNTs composites possess the excellent capacitive behaviors. • CeO₂/MWCNTs composites improve the specific capacitance and the cycle stability. • The ratios of CeO₂ and MWCNTs play major role on capacitive character. Cerium oxide nanoparticles/multi-wall carbon nanotubes (MWCNTs) composites are synthesized by a facile hydrothermal method without any surfactant or template. The morphology and microstructure of samples are examined by scanning electron microscopy (SEM), transition electron microscopy (TEM), X-ray diffraction (XRD), Raman spectrum and X-ray photoelectron spectroscopy (XPS). Electrochemical properties of the MWCNTs, the pure CeO₂, and the CeO₂/MWCNTs nanocomposites electrodes are investigated by cyclic voltammetry (CV), galvanostatic charge/discharge (GDC) and electrochemical impedance spectroscopy (EIS) measurements. The CeO₂/MWCNTs nanocomposite (at the mole ratio of 1:1) electrode exhibits much larger specific capacitance compared with both the MWCNTs electrode and the pure CeO₂ electrode and significantly improves cycling stability compared to the pure CeO₂ electrode. The CeO₂/MWCNTs nanocomposite (at the mole ratio of 1:1) achieves a specific capacitance of 455.6 F g⁻¹ at the current density of 1 A g⁻¹. Therefore, the as prepared CeO₂/MWCNTs nanocomposite is a promising electrode material for high-performance supercapacitors.