NiTiO2 nanoparticles were prepared by the sol–gel method, and a composite film of poly(vinylidene-trifluoroethylene) (PVDF-TrFE)/NiTiO2 was prepared by the solution cast method. The microstructure of NiTiO2 was investigated by transmission electron microscopy (TEM). The film was characterized by TEM, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and dielectric property testing. The results showed that the NiTiO2 nanoparticles were well dispersed in the polymer matrix. With the increase of NiTiO2 content, the crystallinity of PVDF-TrFE/NiTiO2 decreased. The permittivity of the films improved significantly with the increase of NiTiO2 content. The permittivity at 1000 Hz and room temperature increased to 18.56 for PVDF-TrFE/Ni0.1TiO2 (60 wt%) from the value of 11.17 for the pure PVDF-TrFE film. Furthermore, the permittivity of the composite film increased with the increase of temperature.