The paper describes the results obtained on the enhanced electrochromic performance of Tungsten oxide (WO3) thin films assisted by electrospun PVA nanofibers. WO3 was fabricated by spin coating technique with tungsten powder as starting precursor. The effect of electrospun-PVA nanofibers layer on structural, chemical composition, surface morphology and electrochromic properties of the films were characterized by X-ray diffractometer (XRD), X-ray photo-emission spectroscopy (XPS), scanning electron microscope (SEM) and UV-VIS spectrophotometer. The XRD analysis suggested that the crystalline of WO3 can be identified as a monoclinic WO3 structure. XPS investigations also confirmed the existence of characteristic peaks of W. The significant enhancement of electrochromic properties of the films is achieved by additive electrospun-PVA nanofiber layer.