Fabrication of PtRu nanoparticles was conducted by a galvanoslatic pulse electrodeposition technique. We studied various deposition parameters including current on-time and off-time, current density, as well as concentrations for the Pt and Ru precursors in the plating bath in order to determine the optimized process condition for the highest methanol oxidation ability. Cyclic voltammetric profiles were obtained in electrolytes of 0.5 M H
, and mixture of 0.5 M H
and 1.0 M CH
OH to determine characteristics in the hydrogen absorption/desorption and peak currents in the anodic/cathodic scans. We observed that a shorter current off-time resulted in better catalytic abilities when the Pt precursor concentration was increased. Partial dissolution of Ru in the as-deposited PtRu nanoparticles during the current off-time might be responsible.