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Fe and W co-substituted BaTiO 3 perovskite ceramics, compositional formula BaTi 0.5 (Fe 0.33 W 0.17)O 3 , were synthesized by the standard solid-state reaction method and studied by X-ray diffraction, scanning electron microscopy and spectroscopy ellipsometry. The prepared sample remains as double phases with the perovskite structure. The structure refinement of BaTi 0.5 (Fe 0.33 W 0.17)O 3 sample was performed in the cubic double and hexagonal setting of the Fm3m and P6 3 /mmc space groups. Spectral dependence of optical parameters; real and imaginary parts of the dielectric function, refractive index, extinction coefficient and absorption coefficient were carried out in the range between 1.4 and 4.96 eV by using the ellipsometry experiments. Direct bandgap energy of 4.36 eV was found from the analysis of absorption coefficient vs. photon energy. In addition, the oscillator energy, dispersion energy and zero-frequency refractive index values were found from the analysis of the experimental data using Wemple-DiDomenico single-effective-oscillator model.