The invention discloses an array substrate, and a method for repairing a broken data line on an array substrate. The method for repairing a broken data line on an array substrate includes steps: performing a treatment on a part of a semiconductor layer corresponding to an opening in a data line so that the part of the semiconductor layer becomes a conductive region, and the ends of the opening in the data line are electrically connected to each other by the conductive semiconductor layer. The above method for repairing a broken data line provided by the invention is not affected by the linewidth of the data line so that the broken data line can be repaired in the case that the linewidth of the data line is relatively small.