A discharge cut-off valve for an air compressor is provided. The discharge cut-off valve includes a hinged leaf valve within the recessed portion of a cylinder head manifold. The hinged leaf valve is rotatably anchored at a first end to a joint pin and is guided at a second end by a guide pin. In the on-load phase, the hinged leaf valve is seated over an unloader vent opening while a discharge vent opening is uncovered. In the off-load phase, the hinged leaf valve is seated over the discharge vent opening while the unloader vent opening is uncovered. As a result, compressed air is prevented from escaping the discharge port of the air compressor during the off-load phase, obviating the need for a down-stream turbo cut-off valve in an air dryer, for example.