The electronic structure，optical and lattice dynamical properties of CeO2 are studied using first-principles density functional theory taking into account the on-site Coulomb interaction within the LDA+U scheme. Results of the charge density and electron localization function distribution indicate that CeO2 is an insulator with covalent bonding between Ce and O atoms. Calculated dielectric constants，Born effective charge tensors，phonon dispersion curves reproduce the experimental data reasonably.