An active matrix substrate includes: first to third lines formed in first to third line layers, respectively, a signal different from a signal supplied to the first lines and the second lines being supplied to the third lines; first connection lines 21a, 21b that connect the first lines or the second lines with the first terminals; and second connection lines 24c that connect the third lines with the second terminals. One of two adjacent ones of the first connection lines is at least partially formed in one of the first line layer and the second line layer, and the other is at least partially formed in the other line layer. In areas that are in the sealing area and where the first connection lines and the second connection lines are superposed, the two of the first connection lines are at least partially superposed when viewed in a plan view.