This authors introduce the basic principle,data acquisition and processing method of sound wave computerized tomography(sound wave CT),and then makes a detailed discussion on the applied effect of sound wave CT in geological regional detection of an extra large water gushing channel in a certain hydropower station diversion tunnel.Practice shows that sound wave CT can effectively remedy the limitation of single-hole sound wave test,and the result images of sound wave CT describe vividly the position and scale of the gushing channel of ground water.Thus,sound wave CT can successfully detect similar geological problems and provide scientific basis for the follow-up construction design.