The objective of this study is to propose a prediction technique for cooling effect of dry mist, and present useful data for design / control of a dry mist system. In this paper, the cooling effect of dry mist system was verified by two dry mist systems there were actually introduced and operated. One of the verified systems is a dry mist system that was installed into the air corridor on the site Aichi Expo. A cooling effect of this one was evaluated by using the field measurement data during three months. Another one is a dry mist system introduced into N university campus. We found out that the cooling effect by dry mist evaporative is presented about 3 degree Celsius of air temperature reduce and about 15 %RH of relative humidity increase. In addition, the cooling effect of the dry mist system was simulated with a CFD analysis code that is Fluent Ver. 6.3. The reproducibility was confirmed, and the possibility of the performance prediction of the dry mist system was shown.