In order to improve the pixel utilization rate of single projector dome movie system constructed by fisheye lens, the design concept of bi-directional anisotropic digital fisheye projection lens is proposed. By analyzing the characteristics of cylindrical lens, the function relationship of astigmatism and the focal length of cylindrical lens is given, and the focal length distribution relationship in sagittal direction and meridian direction is given. The structure of bi-directional digital fisheye projection lens is analyzed and designed, and gradual changing focal lengths along dimensions are produced by introducing cylindrical lens in lens structure. The lens have different image heights in sagittal direction and meridian direction at the same field of view, finally, the anisotropic mapping law is formed. The optical system of lens contains four sagittal cylindrical surfaces and one meridian cylindrical surface, the ratio of the sagittal image height to the meridian image height is 1.52∶1, with high resolution. Compared with the traditional fisheye lens, the pixel utilization rate of the single projector digital dome screen system constructed by the bidirectional anisotropic digital fisheye projection lens is increased by 52%.