A display panel includes a first substrate, a plurality of pixel units, a plurality of first signal lines, a first testing line and a second testing line. The first signal lines are disposed on a peripheral area and electrically connected to corresponding pixel units. The first signal lines include a plurality of first sets of signal lines and a plurality of second sets of signal lines alternatively arranged. The first and second sets of signal lines are formed on different layers. The first testing line is electrically connected to the first sets of signal lines. The second testing line is electrically connected to the second sets of signal lines.