One of the ways to reduce the size and increase component density in circuits is via the fabrication of devices based on semiconductor nanofibers. We report on the fabrication of an electrospun regio-regular poly(3-hexylthiophene-2,5-diyl) fiber field effect transistor (FET). The hole mobility of the device was calculated to be 4 x 10(-4) cm(2)/V-s and the ON/OFF ratio was similar to 7. The results are compared to those obtained on a thin film FET. The large surface to volume ratio of the fiber makes it susceptible to doping, however, proper handling in an inert environment and pretreatment of the substrates should enhance device performance. Electrospinning is proposed as an easy one step process to fabricate one-dimensional polymer FET's. (C) 2005 Elsevier B.V. All rights reserved.