Qiankou rock ledge is one of the rapid shoals in the upper reaches of the Yangtze River.Based on the analysis of the reasons of navigation obstruction,we study the reef-cutting regulation by model tests.The influence factors of regulation project scheme consist of three depths (4,5 and 6 m) of reef-cutting,two levels (full blasting or partial one) of reef-cutting,and the reef filling tank.The results show that the different depth schemes have the basically same flow pattern,with transverse flow obviously weakened,and without obstruction of navigation.The full cutting scheme reduces the difficulty of navigation mark arrangement,decreases the number of the navigation mark,and reduces the maintenance and operation cost for this waterway section.So the advantages of this scheme are obvious.The bubble swirling water decreases to a certain extent and the flow pattern is further improved after reef-cutting.We recommend the scheme of channel regulation project of 5 m-depth and full reef-cutting blasting with the reef filling tank,because of the effective improvement of the waterway condition and the significant reduction of the waterway maintenance difficulty and operation cost.