We have fabricated P(VDF-TrFE) nanofiber webs by electrospinning. Highly aligned nanofiber webs with high uniformity and a smooth surface were fabricated. To obtain single-crystalline P(VDF-TrFE) nanofibers, we have studied the effect of stretching and annealing on the P(VDF-TrFE) nanofiber web. Three samples were fabricated: as-electrospun, annealed, and annealed after stretching. The single-crystalline P(VDF-TrFE) nanofibers were successfully obtained by stretching and annealing process. (C) 2015 The Japan Society of Applied Physics