Abstract: Investigation on Sodium-ion-conducting polymer nanocomposite electrolyte system based on the polymer blend of poly(ethylene oxide) and polyvinyl pyrrolidone (PEO/PVP), complexed with NaIO4 salt and nanofilled with TiO2 of average size ~10 nm, are presented in this report. The salt complexed polymer blend electrolytes were prepared in the form of dimensionally stable and free-standing thin films (150 μm) by conventional solution cast technique. In the polymer blend, the PEO proportion was 70 weight percent (wt%). In PEO/PVP polymer matrix, the salt NaIO4 and the TiO2 nanofiller were at concentration of 10 wt% and 1 wt%, respectively. Micro Raman and XRD studies confirmed the miscibility between PEO and PVP and the complexation of the salt with PEO/PVP polymer host. TEM measurements were carried out to evaluate the size and distribution of the dispersed TiO2 nanofillers. The complex impedance spectroscopy in the frequency range 1 Hz – 1 MHz at room temperature shows an enhanced ionic conductivity of the four-component PEO/PVP/NaIO4/TiO2 nanocomposite Sodium-ion-conducting polymer electrolyte system.