Photoelectrical mechanism of single Indium Oxide nanowires have been investigated using current-voltage characteristics measurements varying with temperature. The fabricated In2O3 nanowires show high photosensitivity up to 140 at room temperature. It is shown that the photosensitivity of In2O3 nanowires decreases by increasing the temperature due to shorter carrier life time, higher dark conductance and lower electron mobility at higher temperatures. The significantly enhanced photoconduction of single-In2O3 nanowires observed under UV illumination is attributed mainly to the transition from defect levels, which are introduced by the oxygen vacancies that are mostly present on the surface of the nanowires.