The present study proposes the use of a TiO₂ nanotube layer for antireflection coating. The structure, surface morphology and optical property were tested by X-ray diffraction, scanning electron microscopy, spectrophotometer and spectroscopic ellipsometer. The results obtained by fitting ellipsometry spectra in the 450–830 nm range, using a two-sublayers physical model, are in good agreement with the film morphology and in accordance with the optical properties measured. The refractive indices of the top and bottom TiO₂ sublayers were 2.4 and 1.6 (at 600 nm), respectively. The minimum reflectivity obtained was less than 0.1% and the average of 2% in the wavelength the range 450-830 nm.