Abtract: Cuprous oxide(Cu 2 O) were synthesized by a wet-chemical approach in aqueous solution and Pd electrocatalysts supported on cuporus oxide (Pd/ Cu 2 O) and Vulcan XC-72 (Pd/C) were synthesized both via modified sodium borohydride reduction method. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry(CV) methods were used to characterize the surface morphology and composition of Cu 2 O nanoparticles and the catalysts. 10 Linear sweep voltammetry (LSV) and Chronoamperometry (CA) were employed to evaluate the activity and stability of the catalysts. The results showed that Cu 2 O nanoparticles were spherical with smooth surface and the average diameter was about 600 nm. Pd nanoparticles decorated on the surface of Cu 2 O nanospheres and agglomerated slightly and the average size of the Pd nanoparticles was about 10 nm. A certain amount of Copper oxide and the metallic Cu were formed during the preparation of the Pd/Cu 2 O 15 catalyst. The Pd catalyst supported on cuporus oxide (Pd/Cu 2 O) shows the superior performance to the catalyst supported on Vulcan XC-72, which attributed to the two reasons. One was the Pd/Cu 2 O catalyst had the larger surface area and the other was all of the support Cu 2 O itself, Copper oxide and the metallic Cu formed in the process of catalyst preparation have activity to the H 2 O 2 electroreduction reaction to a certain extent.20