A heat exchanger can efficiently perform heat exchange between a low temperature refrigerant and brine and between the brine and hydrogen gas and can reduce the size of cooling equipment and the equipment cost. The heat exchanger comprises: a vacuum insulated container (12) filled with brine; a lid (13) for sealing an upper opening of the container; a rotating shaft (14) disposed in an axis line direction of the container; propellers (15) mounted on the rotating shaft; spiral hydrogen gas cooling pipes (16, 17) disposed in a two-tiered manner around the rotating shaft and the propellers; and refrigerant pipes (18) for cooling the brine disposed around the hydrogen gas cooling pipes.
