Pt was deposited on carbon support by chronoamperometry. The catalytic activity for methanol oxidation was checked by CV (cyclic voltammetry) method. The amount of Pt loading was calculated by integration of I-t curve obtaining the total current used for the Pt deposition. The ECA (electrochemical active surface area) for loaded Pt was calculated from the hydrogen adsorption/desorption peaks in 0.5 M H₂SO₄ solution. Pt was deposited on clean carbon electrode surface with various concentration of Pt. The catalytic activity showed maximum value when a low concentration of Pt solution (0.1 mM) was used. As the concentration of Pt increased, the specific catalytic activity of Pt decreased suggesting that, in the electrochemical reaction of Pt ion with electrode surface, Pt particles were smaller and more dispersed in low concentration of Pt solution. With this condition (0.1 mM Pt), Pt was electrodeposited on a commercial carbon support, Vulcan XC-72. Electrochemically loaded Pt catalyst had the higher ECA, and showed higher specific catalytic activity for methanol oxidation than a commercial Pt/C catalyst.