To smoothly guide circulating cooling water flowing through an air- liquid contact passage in the upper stage to the air-liquid contact passage in the lower stage through a connecting body, to prevent the water from flowing into adjacent exclusive passages of air, to discharge dry air of a desired flow rate from the exclusive passages of air in all stages into air passages of a cooling tower, in parallel with wet air, and thereby to prevent occurrence of white smoke without fail.

The peripheral edge parts of discharge port parts 12d and inlet parts 12e of air-liquid contact passages 12a in the upper and lower stages are inserted into a groove part of a connecting body 13 which is opened in the upper and lower parts and formed of a virtually hollow rectangular parallelepiped, and the air-liquid contact passages 12a in all stages are made to communicate with each other by this connecting body 13 over the total height of an outdoor-air intake.