Abstract: Polyvinylidene fluoride (PVDF) based composites filled with insulating BaTiO₃, semiconductive SiC and conductive graphite nanoplatelet (GNP) were fabricated by simple solution mixing process. The effects of different nanofillers on the dielectric behavior of PVDF-based composites were mainly investigated. The results show that the dielectric constant of PVDF-based composites is found to increase with the increasing of all nanofiller contents, particularly for the composites with semiconductive SiC and conductive GNP fillers. The dielectric relaxation behavior of SiC/PVDF and GNP/PVDF composites can also be verified via ε'-ε" plot, where the relaxation peaks of PVDF-based composites at high frequency region tend to be straight when the content of SiC and GNP reaches the percolation threshold. In addition, the form of dielectric modulus can well describe the relaxation behavior of the PVDF-based composites. The relaxation activation energy reduces with the increasing of nanofiller content, which indicates that the addition of the nanofiller improves the polarization of PVDF-based composites.