The invention discloses a method for identifying dangerous points of buildings along a riverway, and relates to the technical field of mountain flood disaster prevention and control. The method comprises the steps of measuring a basic shape of a riverway section and elevation, longitude and latitude of building points; converting longitude, latitude and elevation values into geographic coordinates; calculating cross section basic water level and flow of a target river section; by utilizing hydraulic slope, obtaining disaster forming flow and cross section water level of any building point M on the cross section; and according to the disaster forming flow of all the building points, judging a most dangerous section or a most easily affected river section of the whole riverway. According to the method, the disaster forming water level does not need to be manually judged, and the disaster forming water level along a river is calculated from a spatial geometrical perspective, so that the disaster forming flow can be conveniently calculated; and if the disaster forming water level exists, the elevation, corresponding to the disaster forming section at a measurement section, of a measured house not on the measurement section can be judged and calculated.