Abstract: When a crossflow water cooling tower is operated, noise made by an air circulating device and water falling down inside the tower is propagated outside. In the conventional cooling towers, however, the main source of the noise, namely the noise of the falling water was very incompletely insulated. The air entering space provided according to this invention and defined by at least a pair of inclined walls and a pair of parallel side walls is in an upward-widening structure whereby the noise produced inside the tower by the flowing and falling water is dissipated upward so as to significantly reduce the noise propagated to the surrounding area.