The present disclosure provides a mask plate, belongs to the field of display technology, and can maintain a uniform exposing interval, so that the exposure pattern has a uniform deformation amount and pattern size. A mask plate comprises opaque regions and transparent regions, and spacers of the same height are arranged in the opaque regions. Another mask plate comprises active regions and dummy regions, and spacers of the same height are arranged in the dummy regions. The present disclosure can be applied in a process for fabricating a color film substrate.