A nanowire device having a structure allowing for formation of p-type and n-type doped portions in a nanowire, and a method of fabricating the same. The nanowire device includes a substrate, a first electrode layer formed on the substrate, a second electrode layer facing the first electrode layer, a plurality of nanowires interposed at a predetermined interval between the first electrode layer and the second electrode layer to connect the same, and an electrolyte containing an electrolytic salt filling spaces between the nanowires.