An oxide semiconductor depositing apparatus includes a heating chamber which is configured to heat and plasma-treat a first substrate including an insulation layer, and includes a chamber body, a heater disposed in the chamber body which is configured to heat the first substrate, and a cathode plate spaced apart from the heater, a high frequency voltage applied to the cathode plate, and a first process chamber which is configured to provide an oxide semiconductor layer on the insulation layer of the first substrate.