Nano-carbon materials, such as carbon nanotubes and carbon nanofibers, are being thought to be used as multifunctional reinforcement in composites. The growing of carbon nanofiber at the carbon fiber/epoxy interface results in composites having better electrical properties than conventional carbon fiber/epoxy composites. In this work, carbon nanofibers were grown in situ over the surface of a carbon fiber fabric by chemical vapor deposition. Specimens of carbon fiber/nanofiber/epoxy (CF/CNF/epoxy) composites were molded and electrical conductivity was measured. Also, the CF/CNF/epoxy composites were tested under flexure and interlaminar shear. The results showed an overall reduction in mechanical properties as a function of added nanofiber, although electrical conductivity increased up to 74% with the addition of nanofibers. Thus CF/CNF/epoxy composites can be used as electrical dissipation discharge materials.