This application relates to a photo-mask and a method for manufacturing an active switch array substrate of the photo-mask. The photo-mask includes a transparent region, a light shielding region, and a semi-transparent region disposed between the transparent region and the light shielding region. A transmittance of the photo-mask is adjusted according to a doping amount and a distribution density of a low reflective material, so as to enable a transmittance of the semi-transparent region to be less than a transmittance of the transparent region and to be greater than a transmittance of the light shielding region.