PURPOSE: To prevent white fuming by using a sealed cooling tower and mixing sucked airs of upper and lower parts of an air suction surface without using a separate unit.

CONSTITUTION: A white fuming preventing apparatus for a sealed cooling tower comprises heat exchanger split to upper and lower parts to form dry and wet airs and to mix them, and a partition 51 provided in a sprinkling tank 5 of a lower stage. Thus, the dry air of the upper part is mixed with the wet air of the lower part thereby to avoid white fuming of the wet air.