The electronic configuration between the interface of supported Rh and CeO 2 (111) surface was investigated by Tight Binding based Ultra Accelerated Quantum Chemical Molecular Dynamics method (TB-UAQCMD) at 1073 K.Time courses of bond energies of Rh-O (-Ce) plots for 5000 fs showed gradual increases of bond strength between oxygen and rhodium atoms in the uppersurface of the CeO 2 (111). This caused the anchoring effect of Rh-O (-Ce) bonds in the form of Rh-O (-Ce). Therefore total energies of the Ce-O bonds in the Rh/CeO 2 were found to become more stable than that in the pure CeO 2 . The activation energy of grain growth of Rh/CeO 2 nanoparticles was estimated by this deviation in these Ce-O bond energies. Experimentally observed suppression in the grain growth of Rh/CeO 2 nanoparticles relative to those without Rh was quantitatively reproduced by three dimensional Kinetic Monte Carlo method (3D-KMC).