A wiring repair apparatus includes an XY stage on which a substrate is placed, a laser source unit disposed above the XY stage, first and second gas windows disposed between the laser source unit and the XY stage, and first and second CVD gas units. The laser source unit emits a laser beam to a part of the substrate to be repaired. This laser beam passes through either the first or second gas window. The first CVD gas unit supplies an Al source gas (DMAH gas) to the first gas window while the second CVD gas unit supplies a Cr source gas (Cr(CO)6 gas) to the second gas window.