The reduction of pentavalent vanadium ions in aqueous solutions upon laser irradiation has been confirmed by using optical absorption and fluorescence techniques. X‐ray photoelectron spectroscopy (XPS) study revealed that V2O5was reduced to lower oxides upon laser treatment. Furthermore, the presence of reduced valence states of vanadium has been detected through XPS in vanadium‐containing solids such as V2O5/P2O5glass, thin films prepared separately from V2O5powder and the glass.