The utility model relates to a corrosion-resistant long-life large-scale motor cooler and a heat exchange system thereof. The motor cooler comprises a heat exchange water tank, a front tube box and a rear tube box, wherein the front tube box is covered at the upper end of the heat exchange water tank and has a hat-shaped structure with one end fully opened and the other end with two symmetric through holes, and the rear tube box is covered at the lower end of the heat exchange water tank and has a hat-shaped structure with one end fully opened and the other end closed. A vertical partition board is arranged in the front tube box and is located at the center of the inner wall of the hat-shaped structure of the front tube box, the space between the front tube box and a tube plate is segmented into two independent spaces by the partition board, and a flow guide arc plate is fixed under one of the two through holes on the inner wall surface of the front tube box. The heat exchange system comprises a large-scale motor, the motor cooler and a cooler outer cover, and two symmetric air guide arc plates are arranged on the inner wall of the cooler outer cover. The sea water corrosion resistance of the cooler is improved, the service life of the cooler is prolonged, and cooling efficiency and operation reliability are improved.