Al-doped ZnO (AZO) high-resistance films with the doping mole fraction between 5%～20% are prepared by Sol-Gel method. The sheet resistance of the films are characterized by the square resistance method. The morphology of the films are characterized by scanning electron microscopy (SEM). Nano Measurer 1.2 software is used to measure the mean particle radius of the film grains, and the spectral transmittance of the film was characterized by a spectrophotometer. When the doping mole fraction of Al is between 5%～20%, the sheet resistance gradually increases between 2～405 MΩ/□, the grain size gradually decreases between 24.35～17.53 nm, and the visible light transmittance can reach about 80%. The liquid crystal lenses with modal control of AZO high-resistance layers with different Al doping mole fraction are prepared and their optical interference characteristics are studied. AZO films with the doping mole fraction between 10% and 15% can meet the requirements of liquid crystal lenses for film transparency and square resistance.