A pixel array is located on a substrate and includes a plurality of pixel sets. Each of the pixel sets includes a first scan line, a second scan line, a data line, a data signal transmission line, a first pixel unit, and a second pixel unit. The data line is not parallel to the first and the second scan lines. The data signal transmission line is disposed parallel to the first and the second scan lines and electrically connected to the data line. Distance between the first and the second scan lines is smaller than distance between the data signal transmission line and one of the first and the second scan lines. The first pixel unit is electrically connected to the first scan line and the data line. The second pixel unit is electrically connected to the second scan line and the data line.