The electronic structure and optical properties of plutonium dioxide were calculated using the generalized gradient approximation with a Hubbard parameter U(GGA+U) for considering the strong coulomb correlation between localized Pu 5f electrons based on the first-principles density functional theory. The calculated results show that PuO_2 is a semiconductor material with the band gap of 1.8 eV, which is in good agreement with the corresponding experimental data. Furthermore, the dielectric function, reflectivity, refractive index, and extinction coefficient were calculated and analyzed using the Kramers–Kronig relationship for PuO_2. The calculated results were compared with the experimental data from the published literature. The electronic structure and optical properties of plutonium dioxide were calculated using the generalized gradient approximation with a Hubbard parameter U (GGA + U) for considering the strong coulomb correlation between localized Pu 5f electrons based on the first-principles density functional theory. The calculated results show that PuO 2 is a semiconductor material with the band gap of 1.8 eV, which is in good agreement with the band gap of 1.8 eV, which is in good agreement with the corresponding experimental data. for PuO_2. The calculated results were compared with the experimental data from the published literature.