A noble metal (NM) can stabilize monolayer-dispersed surface oxide phases with metastable nature. The formed "oxide-on-metal" inverse catalyst presents better catalytic performance than the NM because of the introduction of coordinatively unsaturated cations at the oxide-metal boundaries. Here we demonstrate that an ultrathin NM layer grown on a non-NM core can impose the same constraint on the supported oxide as the bulk NM. Cu@Pt core-shell nanoparticles (NPs) decorated with FeO patches use much less Pt but exhibit performance similar to that of Pt NPs covered with surface FeO patches in the catalytic oxidation of CO. The "oxide-on-core@shell" inverse catalyst system may open a new avenue for the design of advanced nanocatalysts with decreased usage of noble metals.