Abstract The water gas shift catalytic activity and methane selectivity of Pt/CeO2 catalysts are shown to be strongly dependent on the platinum-ceria interaction. Platinum nanoparticles supported on nanostructured ceria rods present a higher hydrogen yield and lower methane selectivity than its counterpart catalysts supported on ceria nanoparticles or nanocubes, despite the similitude in platinum particle size. Indeed, the constraints of the 1D crystal structure of the ceria nanorods and the selective exposure of the (110) crystal plane are directly related to its superior catalytic activity. Platinum nanoparticles do not only act as active sites for CO adsorption and oxidation but also affect the reducibility of the support.