Copper oxide (CuOx) thin film has been deposited on glass substrate using the thermionic vacuum arc (TVA) method. The TVA system works in high-vacuum condition. The microstructural, surface, and optical properties were investigated. Reflection planes corresponding to Cu2O, CuO, and Cu crystal networks were detected in the x-ray diffraction (XRD) pattern. According to the XRD results, the deposited thin film was in polycrystalline form. The grain size, Miller indices, dislocation density, and microstrain were calculated. The crystalline size obtained from the CuO reflections was approximately 20nm. The average roughness of the deposited film was measured to be 1.8nm. The height distribution function of the grain size on the deposited surface was determined, revealing a mean grain height of 11nm. The deposited film exhibited high transparency in the ultraviolet-visible (UV-Vis) spectroscopic region. The refractive index of the film was measured to be 2.20 at 632nm. The optical bandgap and real part of the dielectric constant were found to be 1.5eV and 4.84, respectively.