Nanostructured Pt/CePO4 thin-film electrodes consisting of the Pt nanocrystallites and amorphous CePO4 were synthesized by sputtering, and the enhanced electrooxidation properties of methanol were investigated. Compared to a bare Pt electrocatalyst, the Pt/CePO4 nanocomposites exhibited remarkably higher activities. The improved catalytic activities were observed even after normalization by the electrochemical surface area. This can be explained by both the bi-functional effect of CePO4 and the modified electronic structure of Pt by the charge transfer from CePO4 to Pt.