One or more embodiments provides a mask assembly including a frame defining an opening, a mask stick above the frame, extending in a first direction, defining through-holes, and including pattern areas that include one or more first non-hole portions in which no through-hole exists, and one or more second non-hole portions in which no through-hole exists, and a first support stick between the frame and the mask stick, extending in a second direction crossing the first direction, and overlapping the one or more second non-hole portions.