PtNi nanoparticles are grafted onto three different metal oxide supports, namely MnO₂, MnO₂+TiO₂ and MnO₂+NiO_. Subsequently, their activity for oxygen reduction reaction (ORR) and borohydride oxidation reaction (BOR) in alkaline media was studied using voltammetric techniques. The dependence of electrocatalysts behavior on reaction conditions, such as electrolyte temperature, was also evaluated. ORR and BOR kinetic parameters, namely Tafel slopes, kinetic current densities, and activation energies, were determined from the obtained data in order to compare the performance of the three electrocatalysts prepared. These results show that PtNi anchored on metal oxide supports possess electrocatalytic activity for ORR and BOR in alkaline media, which suggests potential application of these materials in direct borohydride fuel cells.