With the promise of its high conductivity, the ceramic Li1.3Al0.3Ti1.7(PO4)(3) (x=0.85) of Li3-2x(Al1-xTix)(2)(PO4)(3) (x=0.55 to 1.0), as a lithium fast ionic conductor, is produced by a conventional solid-state reaction and introduced into the poly(ethylene oxide) (PEO)-based composite polymer electrolyte films (CPE) to improve their ionic conductivity. The CPE films are prepared by a solution-cast technique and their characteristics are investigated by several experimental techniques including X-ray diffraction (XRD), infrared (IR) spectra, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). As measured by electrochemical impedance spectrum (EIS) measurement, the temperature-dependent ionic conductivity of PEO-Li1.3Al0.3Ti1.7(PO4)(3) film with EO/Li = 16 is maximized at 2.631 x 10(-6) S cm(-1) at room temperature and at 1.185 x 10(-4) S cm(-1) at 343 K, while the ionic conductivity of the PEO-LiClO4-Li1.3Al0.3Ti1.7(PO4)(3) film with EO/Li = 8 is maximized at 7.985 X 10(-6) S cm(-1) at room temperature and at 1.161 X 10(-3) S cm(-3) at 373 K when Li1.3Al0.3Ti1.7(PO4)(3) content is 15 wt.%. (c) 2005 Elsevier B.V. All rights reserved.