The classification of the navigation flow conditions at the confluence of a large-scale water drop project group on an artificial canal can pave the way for the selection of several typical water drop projects as the key research objects for numerical simulation or physical model tests and provide technical support for the subsequent comprehensive navigation safety evaluation of the water drop project group.The navigation flow conditions at the confluence of a water drop project mainly depend on quantitative influencing factors，such as the confluence ratio，confluence angle，flow，weir width，and water depth of the main channel，and the type of the confluence layout.The evaluation index for classifying the complexity of navigation flow conditions constructed on the basis of the quantitative influencing factors can quantitatively reflect the complexity of the navigation flow conditions at the confluence.Using the minimum-maximum standardization method and the K-means cluster analysis method，the paper classifies the water drop project group in the Yangtze-Huaihe communication section into four categories according to the evaluation index.Then，it selects 18 typical water drop projects with highly complex navigation flow conditions and highly representative types of confluence layouts from the 50 water drop projects as the key research objects.These typical water drop projects are in a relatively balanced distribution in various types of confluence layouts.