One-dimensional semiconductor nanofibers are regarded as ideal materials for electronics due to their distinctive morphology and characteristics. In this work, La-doped indium oxide (LaInO) nanofibers are fabricated as the channel layer to reduce O vacancies and the density of interface trap states; this is clearly confirmed by investigating the stability under positive bias stress and the capacitance-voltage for field-effect transistors (FETs). The In2O3 nanofiber FETs optimized by doping with 5 mol% La exhibit excellent electrical performance with a mobility of 4.95 cm2 V-1 s-1 and an on/off current ratio of 1.1 × 108. In order to further enhance the electrical performance of LaInO nanofiber FETs, ZrAlO x film, which has a high dielectric constant, is employed as the insulator for the LaInO nanofiber FETs. The LaInO nanofiber FETs with ZrAlO x insulator have a high mobility of 13.5 cm2 V-1 s-1. These findings clearly indicate the great promise of La-doped In2O3 nanofibers in future one-dimensional nanoelectronics.