Wade project research and design need the underwater topographic map analysis,through which,we will know the statistical terrain features and understand the change of river bed,and then carry out targeted dredging and building of regulation structures.In the process of underwater topography analysis,selection of interpolation method is particularly important,because its precision directly influences the analysis results of back silting and river bed change regularity.At present,there are many studies on interpolation methods,but there is a lack of data grid processing in the terrain analysis.We compare the accuracy among various interpolation methods,and provide reference for the selection of interpolation methods.