Thin-film transistors (TFTs) were fabricated using a 20-nm-thick indium molybdenum oxide (IMO) semiconductor layer at room temperature. The grazing incidence x-ray diffraction patterns confirmed that the deposited films are amorphous. The average transmittance (400-2500 nm) and the optical band gap are ~ 88% and 3.95 eV, respectively. The TFTs fabricated on glass substrates showed a saturation mobility of 4.0 cm²/V·s with an I _ON/ I _OFF ratio of 2 × 10³ and a threshold voltage of -1.1 V, which are encouraging preliminary results in order to develop IMO as high-performance semiconductor layer.