The invention discloses a method for drawing a dam contour line based on a cubic interpolation method, which comprises the following steps of: selecting sections of a dam along a river direction and atransverse river direction as typical sections for measuring point prediction, establishing a finite element model of the dam in Hypermesh, performing grid division, and exporting grid node numbers and corresponding coordinate information of the typical sections; reading known measuring point coordinate information and measuring point measuring values of corresponding coordinates in a dam monitoring cloud platform database; based on a support vector machine algorithm, with the known measuring point coordinate information read from the dam monitoring cloud platform database as an independent variable and the measuring point measured value of the corresponding coordinate read from the dam monitoring cloud platform database as a target variable, performing nonlinear training; importing the parameters into the trained model, and solving predicted values of the corresponding nodes; drawing a monitoring point measured value contour line; and visualizing the drawn contour map.