CeO2thin films were grown on Si(100) and Si(111) substrates by radio frequency-magnetron sputtering. The growth temperature and the substrate orientation have significant influences on the preferred orientations of depositedCeO2films. X-ray diffractometry and transmission electron microscopy analyses showed thatCeO2on Si(111) has a better preferred orientation in the direction of the substrate orientation thanCeO2on Si(100).CeO2films deposited on Si(111) substrates maintain a preferred orientation better thanCeO2films on Si(100), when they are subjected to annealing at 900 °C inO2atmosphere for 30 min. Rutherford backscattering spectra taken ofCeO2/Sibefore and after annealing showed thatCeO2has strong thermal stability.