Polyvinyl Chloride (PVC) was blended with nitrile-butadiene rubber (NBR) in different ratios. The influence of different concentrations of nanosized filler (graphite and copper) on the properties of PVC/NBR blends using solution casting method was studied. The results obtained from the mechanical properties show that elongation at break increases with increasing NBR content in the (PVC/NBR) blends, while tensile strength values decreases as the filler concentration increases in all composites. The dielectric properties of these samples were studied by means of broadband ac-relaxation spectroscopy in the frequency range between 0.01 Hz to 10MHz and at 25dC. The dielectric properties and the conductivity were found to be influenced by increasing the content of both fillers. According to the values of conductivity, the nanocomposite of PVC/NBR (50/50) filled with 5;copper belongs to materials characterized as semiconductors.