The electrical levels of defects of high-k dielectric ZrO2 films deposited with different oxygen fluxes have been investigated using x-ray diffraction, x-ray photoelectron spectroscopy, and spectroscopic ellipsometry. Various defects with the formation of interstitial oxygen and oxygen vacancies existed in monoclinic ZrO2 films. The optical properties of the films are strongly influenced by configuration changes in defects. Parameters were extracted from spectroscopic ellipsometry raw data by Lorentz oscillator model fitting that indicate the probabilities and transition energies for different charged oxygen interstitial and vacancy defects. These correspond to the electron affinity energies calculated by density functional theory and assigned to electrons trapped at different charged defects from the bottom of the conduction band. A nondestructive and noncontact solution is suggested for detecting the defect states and energy level of high-k film.