The thin-film transistors (TFTs) based on amorphous-InSnZnO (a-ITZO) as the active layer are prepared by RF magnetron sputtering at room temperature. The conditions for the preparation of a-ITZO TFT are optimized in terms of sputtering gas ambiance, active layer thickness, annealing ambiance, annealing temperature and annealing time. A decent a-ITZO TFT with a field-effect mobility of 9.03 cm2/Vs, a subthreshold swing of 230 mV/dec and an on/off ratio of 5.72 ×107 is obtained at a low annealing temperature of 150 ℃. The test results provide the experimental basis for low-temperature annealing of a-ITZO TFTs for future flexible applications.