In this work, poly (vinylidene fluoride), PVDF, was mixed with nanoparticles of perovskite structure, Na1/3Ca1/3Bi1/3Cu3Ti4O12, synthesized by solid state reaction, in order to obtain a nanocomposite that can be used as a supercapacitor. The dielectric properties were measured and the variation of this property with the increase of nanoparticle content was studied in our previous work. The existence of polymorphism in PVDF usually is a reason for the variation of the dielectric properties of this material. Studies of the literature usually attribute good dieletric properties to the PVDF ß-phase, which is obtained by the application of high elongation rates from the melt or solution. However, in our previous work, only the α-phase was obtained. Thus, in this work, a method to obtain the ß-phase in the PVDF/perovskite nanocomposites was developed through the thermal uniaxial deformation of the nanocomposite from the melt and solution. Samples that were elongated and samples that were not were prepared; characterization with FITR and WAXS analyses were done to verify the β-phase presence and with DSC to quantify the β-phase fraction. The dielectric properties of both samples were also measured and compared to analyze the improvement of the dielectric properties due to the presence of the β-phase.