Herein, structural and optical properties in vanadium oxide layers were evaluated by means of different spectroscopic tools, such as X-ray diffraction (XRD), X-ray reflectivity (XRR), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS) absorbance or photoluminescence (PL). The relationship between crystal structure and optical properties was carefully evaluated in vanadium oxide layers obtained by SPT and RF-MS at different synthesis parameters. A different bandgap for the samples obtained by RF-MS was attributed to the V 4 + oxidation states.