PEO-PANI/TiNPs nanocomposite films with different concentrations of TiNPs were deposited on the glass substrates using a simple casting method. The structural, thermal, morphological, optical, and electrical properties of these nanocomposite films were studied. The amorphous phase becomes dominant when TiNPs are added to the polymer blend, supporting the physical interactions between the polymer chains and TiNPs. The melting enthalpy decreased gradually from 100.6 J/g to 63 J/g by adding 16 wt% of TiNPs in the nanocomposite films; in contrast, the melting temperatures increased. A change in the surface morphology of the PANI/TiNPs nanocomposite films was found, and changes in the optical spectra, band gap energy, refractive index, and electrical conductivity accompanied it. For instance, the sheet resistance ( R s ) of the PEO-PANI film is 2.31 × 10 8 Ω/sq, and this value decreases continuously to 4.85 × 10 7 Ω/sq with increasing the TiNPs concentration up to 16 wt%. At the same time, the electrical conductivity ( σ ) value of PEO-PANI/TiNPs increases from 4.33 × 10 −5 S/cm to 1.38 × 10 −4 S/cm.