The invention discloses a power line three-dimensional reconstruction method based on point cloud data. The method comprises the steps of 1, determining a power line three-dimensional reconstruction model; step 2, determining a polynomial forming a three-dimensional reconstruction model of the power line; step 3, determining the fitting frequency of the three-dimensional reconstruction model of the power line; and step 4, power line point cloud reconstruction: after the fitting frequency of the power line three-dimensional reconstruction model is determined in the step 3, determining the powerline three-dimensional reconstruction model, and according to the model, carrying out sampling calculation at intervals of 0.1 m along the x direction to complete the power line point cloud reconstruction. Through the method, the problems of non-uniform model expressions, relatively complex algorithm compilation and the like in power line point cloud modeling can be solved. A solid foundation islaid for dangerous point detection, wire sag analysis and wire icing and windage yaw calculation based on power line point cloud data.