Ag@TiO₂ core–shell nanoparticles were synthesized as fillers using a simple vapor-thermal method. Based on the nanoparticles, the P(VDF-HFP)/Ag@TiO₂ hybrid films were first prepared by embedding Ag@TiO₂ nanoparticles in a poly(vinylidene fluoride co-hexafluoropropylene) [P(VDF-HFP)] matrix. Microstructural and thermal analysis confirmed that Ag nanoparticles had been successfully coated by TiO₂ shells and that the thickness of the shell layer was about 8–10 nm. The Ag@TiO₂ nanoparticles act as nucleation sites to promote crystallization of the polymer matrix without changing its structure. The P(VDF-HFP)/Ag@TiO₂ composite exhibited enhanced dielectric properties over a wide frequency range, and the dielectric permittivity of the polymer nanocomposites is enhanced by ∼300% over the P(VDF-HFP) matrix at a low filler loading of 10 vol%. Moreover, P(VDF-HFP)/Ag@TiO₂ also exhibit a higher dielectric constant than P(VDF-HFP)/Ag, P(VDF-HFP)/TiO₂ and P(VDF-HFP)/Ag/TiO₂ blend composites while maintaining a low loss tangent (below 0.03 at 1 kHz) to achieve a duplex polarization effect.