Electrospun polyvinylidene fluoride (PVdF)/polyvinylpyrrolidone (PVP) nanofiber embedded with carbon black nanoparticles (<50nm) were fabricated and characterized for supercapacitor separators. Carbon black nanoparticles with different weight percentages (0, 0.25, 0.5, 1, 2, and 4wt%) were added to a mixture of N, N-dimethylacetamide (DMAC)/acetone and sonicated for a well dispersion. Then, PVdF and PVP were added, and the solution was heated on a hot plate to make a polymeric solution prior to the electrospinning process. The morphology of the electrospun nanofibers was characterized by scanning electron microscopy and transmission electron microscopy. Fourier transform infrared spectroscopy was carried out on the PVdF/PVP films to identify changes in the crystalline phase during the process. The annealed nanofibers samples were also examined by X-ray diffraction unit. These investigations demonstrated that the many physical properties were significantly improved, which may be useful for supercapacitor separators. Supercapacitors will become one of the most suitable energy storage devices in the near future, and the separator is one of the major components of the supercapacitors.Keywords: Electrospun Nanofibers, PVdF, carbon black nanopowders, characterization, supercapacitor separators.