The present invention is to provide a machine and a method for suctioning and exhausting air from a storage tank for sand in a molding machine that has less on-off valves and prevents sand from adhering to the interior of the valve for exhausting air while the air is being exhausted. The machine for suctioning and exhausting air from the storage tank for the sand in the molding machine comprises a storage tank for sand in the molding machine, a porous body that is provided in the storage tank for sand and that is distant from an inner face of the storage tank for sand, an empty chamber that is formed by an outer face of the porous body and the inner face of the storage tank for sand, a seal that is placed at a rim of a tip of a nozzle of the storage tank for filling sand and that expands when compressed air is supplied inside the seal, a pilot-operated valve for both suctioning and exhausting air that is fluidly connected to the empty chamber, and an on-off valve that is fluidly connected to the pilot-operated valve for both suctioning and exhausting air and connected to an inside of the seal.