Combining with the natural condition of Jiangyin channel，we analyze riverbed evolvement，channel conditions and economic benefits of Jiangyin waterway，research the feasibility of opening up subchannel in lower section of Jiangyin waterway，and propose the corresponding opening scheme. The results show that the lower section of Jiangyin waterway has the conditions of opening up a certain grade subchannel according to the existing natural condition and using a certain water level. Although the conditions of Jiangyin waterway are good in recent years，the channel relationship is complex. It is suggested to open subchannel of grade I-4，the channel dimension is determined according to the requirements of navigable 3，000-tons sea vessel and 7，000-tons inland vessel，and the virtual navigation mark is used to navigation mark.