The disclosure provides a mask plate and a manufacturing method thereof. The mask plate includes at least one pattern region, each pattern region includes a first opening region and a second opening region which are adjacent to each other along a lengthwise direction of the mask plate, each of the first opening region and the second opening region has a plurality of pattern openings penetrating through the mask plate along a thickness direction of the mask plate, a ratio of a sum of areas of the pattern openings in the second opening region to a total area of the second opening region is greater than a ratio of a sum of areas of the pattern openings in the first opening region to a total area of the first opening region, the first opening region has grooves not penetrating through the mask plate.