The novel manufacturing method for gray-scale masks based on the spatial light modulator has been proposed. In this paper, the basic principle of this method was analyzed, and the corresponding experimental system was fabricated. At the same time, the gray-scale masks of some binary optical elements such as blazed grating, Fresnel lens and Dammann grating have been actually fabricated. This system has intrinsic parallel characteristic owing to its stepper exposure mode, therefore it can improve the manufacturing speed and precision of gray-scale masks with low cost.