By the method of matrix optics, the formation process of ghost images from the residual reflection when beam passes through a single lens is analyzed and the relation between the localities of the ghost images and the curvature radius of the lens is achieved. From the relation, the localities of the ghost images can be determined by designing the curvature radius of the lens. The ghost images analysis is simplified considering the distribution characteristics of the beam path in high-power laser facility, based on which the distribution of the ghost images in the main amplification section is analyzed by the special software. By changing the curvature radius or tilting the lens, with the principles of avoiding the ghost images and minimizing the aberration, the curvature radius of the lens used in the main amplification section is selected as 1∶3 with a shape of crescent and convexity in the direction of more concentrated optics. The method proposed can also be applied to the lens design in high-flux complicated optics system.