In this paper, the pulsed laser deposition (PLD) method was used to prepare Ga-doped ZnO (GZO) nano-films on single-crystal silicon (111) and quartz glass substrates, and the effect of oxygen pressure on the quality of the films was studied. The crystal structure and surface morphology of the films were characterized by X-ray diffractometer and scanning electron microscope. The results show that the average particle size of the nano-film can be controlled by adjusting the oxygen pressure. When the oxygen pressure is 0.01 Pa, the crystal quality of the films is the best. The PL spectrum analysis results show that a proper amount of oxygen in the reaction atmosphere can effectively reduce the defect density and realize the regulation of the luminescence properties of the GZO film. The transmission spectrum analysis results show that the average optical transmittance of the GZO films at 400~800 nm exceeds 85%, then it has good light transmission performance.Hall test results show that when the oxygen pressure is 0.01 Pa, the resistivity of the GZO film is the lowest 2.77×10-4 Ω·cm. With the oxygen pressure continuing to increase, the resistivity of the film was increases, and the carrier concentration and Hall mobility were fell.