Direct alcohol fuel cells' performance is significantly affected by the phase and composition of the catalyst, thereby the development of high-performance alcohol oxidation catalysts is essential. In this study, PVA preparation was used for the first time to create PdCu core-shell nanoflowers with a high electrochemically active surface area and a potent synergistic effect. Notably, the presence of PVA causes Pd and Cu nanoparticles with different reduction rates to form a core-shell structure, and the Pd nanoparticles continue to migrate regularly under the action of PVA, forming a flower-like morphology with a high degree of branching. Cu@Pd22.3 catalyst exhibited 13 times higher catalytic performance (4353.04 mA mgPd−1) than Pd/C (334.09 mA mgPd−1) in ethylene glycol oxidation reaction. The Cu@Pd22.3 catalyst also exhibits higher stability than commercial Pd/C in stability tests lasting up to 20,000 s. This core-shell combination and highly branched structural design result in more active sites for fast ion adsorption/desorption,offering an original method to improving the activity and endurance of polyol oxidation.