To restrict acceleration of icing in an inlet and packing materials in a cooling tower by improving sprinkling equipment.

In a cooling tower A, the number of sprinkling holes 14a are made more on the side of an outside-air inlet 11, and less on the side of a mixing chamber 13. Referring to the volume of water sprinkled from the hole 14a, the circulating cooling-water is sprinkled more on the side of the inlet 11 than it is on the side of the mixing chamber 13. Thus, temperature of circulating cooling-water becomes uniform all over a packing board B, and preferably the temperature is somewhat higher on the side of the part 11 than it is on the side of the chamber 13, and the circulating cooling-water is prevented from being overcooled on the side of the inlet 11. Thus, icing is prevented on the side of the louver of the inlet 11 coming into contact with the outside air and between the filling boards B on the side of the part 11. Complete icing in the coldest time of the year is prevented. The cooling tower A is continuously operated, circulating cooling-water at a predetermined temperature.