Carbon Nanocapsules (CNCs) were investigated for their electrocatalytic performances for the oxygen reduction reaction in alkaline electrolyte. With an average diameter of 10-30 nm, the CNCs are composed of graphene layers encapsulating a hollow core. A gas diffusion electrode (GDE) made of CNCs revealed a much enhanced i-V polarization response than that of Vulcan XC72. However, its performance was moderately lower than that of Black Pearls 2000. In addition, the CNCs were impregnated with nanoparticles of Ag, MnO x and CoO x . The i-V and galvanostatic results of the catalyzed CNCs indicated significant improvements over that of noncatalyzed CNCs. For example, a Ag-CNC derived GDE was capable of delivering 1.03 and 0.88 V at current densities of 100 and 200 mA cm-2, respectively. Our study offers direct evidence that the CNCs not only exhibit unique electrocatalytic abilities but also function superbly as an electrocatalyst support.