The quantitative study on the film surface morphology is important for the understanding of thin film growth mechanism. The ZnO:Ga (GZO) transparent conductive film is prepared by pulsed laser deposition (PLD). Since this GZO film growth is far from equilibrium, the GZO film has self-affine fractal characteristics and can be described by height-height correlation function H (r, r+ρ). By using atomic force microscope to get the height data of the surface image, the quantitative analysis of height-height correlation function of the GZO film prepared by PLD is carried out. The values of the three important parameters W, ξ and α are measured and it is suggested that the growth of GZO thin film is consistent with Kuromoto-Sivashinsky growth model.