Electrospun metal oxide nanofibers have been regarded as "promising blocks for large-area, low-cost, and one-dimensional electronic devices. However, the electronic devices based on electrospun nanofibers usually suffer from poor performance and inferior Viability. Here, we report an efficient photochemical process using UV light generated by a high-pressure mercury lamp to promote the electrical performance of the nanofiber-based electronic devices. Such UV treatment can lead to strong photochemical activation of electrospun nanofibers, and therefore, a stable adherent nanofiber network and electronic clean interface were formed. By use of UV treatment, high-performance indium oxide (In2O3) nanofiber based field-effect transistors (FETs) with highly efficient modulation of electrical characteristics have been successfully fabricated. To reduce the operating voltage and further improve the device performance, the In2O3 nanofiber FETs based on solution-processed high-k AlOx dielectrics were integrated and investigated. The as-fabricated In2O3/AlOx FETs exhibit superior electrical performance, including a high mobility, of 19.8 cm(2) V-1 s(-1), a large on/off current ratio of 10(6), and high stability over time and cycling. The improved performance of the UV-treated FETs was further confirmed by the integration of the electrospun In2O3/AlOx FETs into inverters. This work presents an important advance toward the practical applications of electrospun nanofibers for functional electronic devices.