In fuel cells, Pt is often employed as an electrode material to facilitate electrochemical reaction processes, in which morphology plays an important role. In this work, three kinds of Pt flowers have been prepared on a glassy electrode substrate via a facile electrochemical deposition in a solution of H3PO4; by controlling work potentials at -0.1 v, -0.2 V and -0.3 V, cauliflower-like, needle-like and rose-like shapes of Pt micro/nanoparticles as confirmed by SEM and XRD are obtained, respectively. Taking methanol oxidation as a model reaction and using CO stripping voltammogram in an acid medium, the electrocatalytic performance of as-prepared three Pt flowers has been evaluated. The three Pt flowers show different electrocatalytic activities, and the needle-like Pt flowers present the highest catalytic activity for electrooxidation of methanol and CO. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.