We report the action of gold as catalyst for the modification of phase from triclinic WO3 to monoclinic W18O49 and nucleation centre for the formation of W18O49 phase, in gold incorporated tungsten oxide films prepared by RF magnetron sputtering technique. A new band is observed near 925 cm(-1) in the Raman spectra of gold incorporated tungsten oxide films which is not observed in the pure tungstenoxide film. The intensity of this band enhances with gold content. A localized surface plasmon resonance (LSPR) band is observed near the wavelength 604 nm in gold incorporated tungsten oxide films. The integrated intensities of LSPR band and Raman band (similar to 925cm(-1)) can be used for sensing the quantity of gold in the Au/WO3 matrix. (C) 2016 Elsevier B.V. All rights reserved.