ITO film and preparation method thereof

The invention relates to an ITO film and a preparation method thereof. The preparation method of the ITO film comprises the following steps: providing a glass substrate, heating the substrate, maintaining the substrate at 220-310 DEG C in an atmosphere of an oxidizing gas and preparing the ITO film on the substrate, wherein the oxidizing gas is selected from one of N2, NO and NO2 or one of a mixed gas of Ar and N2, a mixed gas of Ar and NO and a mixed gas of Ar and NO2. The method has the beneficial effects that the oxidizing gas is adsorbed in an ITO film layer, thus reducing the number of carriers in the ITO film layer, reducing the gap resistance in the ITO film layer and avoiding changing the film layer resistance and the gap resistance as the ITO film layer adsorbs a reducing gas; the resistance of the ITO film layer is kept stable, thus solving the problem of resistance reduction, avoiding the problem that the resistance reduction amplitudes and positions do not have regularity and better controlling th