The electrospinning method was used to fabricate nanostructures of Nafion-poly(vinyl alcohol) (PVA) and Nafion-poly(ethylene oxide) (PEO). Depending on the ratio between the two polymers, nanospheres and/or nanofibers could be obtained in a reproducible manner. The Nafion-PVA mats were found to be more conductive than the Nafion-PEO ones, possibly because of their better mechanical properties when swollen by water. The fiber morphology was always found to be more conductive than the sphere morphology. However, all electrospun mats presented ionic conductivities slightly lower than extruded Nafion 115 or Nafion-PVA cast films.