A wired circuit board includes a metal supporting board, an insulating base layer formed on the metal supporting board, a conductive pattern formed on the insulating base layer, a first semiconductive layer formed on a surface of the insulating base layer exposed from the conductive pattern, an insulating cover layer formed on the conductive pattern and the first semiconductive layer and a second semiconductive layer formed on a surface of the insulating cover layer. The first semiconductive layer is electrically connected to the conductive pattern and the metal supporting board, and the second semiconductive layer is electrically connected to the metal supporting board.