Abstract: The water area before the dam is the place of densely fish. During the third roller compaction concrete cofferdam of the Three Gorge Project (the 3rd RCC) removing, the blasting shock wave would hurt the fish nearly. A series of researches and tests were put into effect to ensure the security of the fish. Radiocoustic position finding and highvoltage pulse action driving away as a designate plan was put into effect. The plan was carried out smoothly in June 6, 2006. The monitor data show that no fish were hurt. The facts show that it was a success fish protective measure.

Key words: the Three Gorge Project, the 3rd RCC, blasting, fish protective measure