The utility model provides a mask plate, including the sub - mask plate of stop part and a plurality of concatenation setting, the stop part covers the clearance between the adjacent sub - mask plate at the planar front projection shadow in sub - mask plate place, and the material of stop part is nonmagnetic material. In evaporation process, the produced magnetic force of magnetic force subassembly can not produce suction to the stop part, and the effort can not applyed by antithetical phrase mask plate to corresponding stop part, consequently, can reduce the deflection at sub - mask plate's edge, avoids sub - mask plate to take place to warp or the fold to it is bad to avoid the backplate to produce the colour mixture, and then improves vapor deposition process's yield.