Abstract: The present application relates to a mold for substrate surface functionalization. In the mold, a rubber strip is provided between an upper mold plate and a lower mold plate in a clamping manner, and a fastening structure enables the upper mold plate and the lower mold plate to clamp in opposite directions, such that the rubber strip, the upper mold plate and the lower mold plate form a mold cavity together under the action of a clamping force; and a positioning structure is used for fixing a substrate in the mold cavity, such that a pouring space is formed between at least one side surface of the substrate and the upper mold plate and/or the lower mold plate, the pouring space being used for pouring a modified material for surface functionalization of the substrate. The present invention further relates to a method for substrate surface functionalization.