A rod coil triblock copolymer consisting of a poly(3-hexylthiophene) (P3HT) rigid block, a styrene coil block, and a coil block with fullerene pendant group has been synthesized (see figure). Nanofibers in films reach 250 nm in length and 10.7 nm in width. Photo- and dark-current imaging by conducting atomic force microscopy reveals that the fibers are highly conductive. The electron and hole mobilities are comparable with a P3HT:fullerene-derivative blend.