TiO₂ nanowire arrays are often utilized to prepare high performance polymer nanocomposites, however, the contribution to the energy density is limited due to their non-ferroelectric characteristics. A nanocomposite with an optimized nanowire array combining the ferroelectric properties of lead zirconate titanate (PZT) with TiO₂, readily forming nanowires (denoted as a TiO₂-P nanowire array), is prepared to enhance the permittivity. Poly(vinylidene fluoride) (PVDF) is used as the polymer matrix due to its high breakdown strength, e.g. 600–700 kV mm⁻¹. As a result, the permittivity and breakdown electric field reach 53 at 1 kHz and 550 kV mm⁻¹, respectively. Therefore, the nanocomposites achieve a higher discharge energy density of 12.4 J cm⁻³ with excellent cycle stability, which is the highest among nanocomposites based on a nanowire array as a filler in a PVDF matrix. This work provides not only a feasible approach to obtain high performance dielectric nanocomposites, but also a wide range of potential applications in the energy storage and energy harvesting fields.