Polyvinylbutyral (PVB) is a thermoplastic polymer extensively used in the production of security laminates, adhesives, and paints, mainly in the military industry, due to its transparency combined with the mechanical resistance, flexibility and adhesive capability. These characteristics of makes PVB a good candidate for multifunctional materials, for example, composites with nanocarbon reinforcements for electronic applications. In this work, nanocomposites of PVB matrix reinforced with graphene nanoplatelets (GNP) and graphene oxide (GO) (PVB/GNP and PVB/GO) were synthesized ‘in situ’ with different concentrations of graphene and graphene oxide. Nanoplatelets of GO and GNP were produced and characterized by X-ray diffraction and transmission electron microscopy (TEM) analyses. The results of infrared and Raman spectroscopies of the nanocomposites showed the presence of interactions between the OH groups of PVB and GO and GNP, but more pronounced for GO. The values of glass transition temperature had an increase of 10 ºC for the nanocomposite with 2.5 wt% GO. The mechanical dynamics analysis showed that the best mechanical behavior was for the nanocomposite with 2.5 wt% GO, possibly due to the interactions and better dispersion of the reinforcement in the PVB matrix. The presence of a shoulder in DMA graphs indicates the presence of polyvinylalcohol in the nanocomposites, and therefore a change in the degree of acetylation of PVB. The SEM and TEM images show a more homogeneous dispersion in the case of OG nanocomposites. Electrical impedance spectroscopy analysis showed that despite a homogeneous dispersion, no significant increases were observed in the values of electrical conductivity. PVB is an insulating polymer and it is believed that the concentrations of OG / GNP used were not sufficient to make nanocomposites really conductive.