The metal-support interaction on the chemical reactivity is illustrated here by density functional theory calculations for the hydrogenation of crotonaldehyde on Pt-13 clusters deposited on CeO2(111). Adsorption of crotonaldehyde on the supported cluster is globally strengthened, compared to Pt(111), both on top of the cluster and at the interface with ceria. The activation barriers of the first and the second hydrogenation steps at both C=C and C=O bonds are consequently increased, but particularly at C=O on top of the cluster, with respect to Pt(111). In contrast, the hydrogenation at C=O is far easier at the interface with ceria, which underlines the key role of the support. The considered model shows a preferential route toward the formation of the saturated aldehyde, in contrast to the measurements. This study paves the way to advanced theoretical models with larger nanoparticles supported on reduced ceria in realistic conditions of environment. (C) 2015 Elsevier Inc. All rights reserved.