After the severe tropical storm Mindulle Landed on Leqing, Zhejiang Province several hours,the blast was suddenly blowing over Taihu lake 300km far from the storm Mindulle. The wind speed of Taihu lake reached 29.3m·s^-1 at the southern bank of the lake at 1300 July 3,2004 observed at an auto-weather station, which exceeded the maximum speed of the storm center and its path region. It has never appeared such event in Huzhou,and rarely appeared in typhoon record. It is studied that the physical mechanism of the strong wind appears over Taihu lake area.