The invention relates to a laser data-based substation foreign object identification method. At present, foreign object recognition is easily affected by environments, modeling is complex, and algorithms are time-consuming. The method of the present invention includes the following steps that: a laser radar is adopted to collect laser data in a plurality of regions; a model point cloud set is built through analysis and settlement; the laser radar is used to collect the laser data of a certain region to be measured, so that the laser data can form test point cloud; outlier removal filtering isperformed on point cloud distribution information through calculation; the distribution histograms of point cloud data in an x-axis direction, a y-axis direction and a z-axis direction are put into statistics; key points are extracted through uniform sampling filtering, and feature vectors are calculated; kdtree matching pair indexes are established; conversion matrix solving is performed throughSVD; the coordinates of the test point cloud are converted, and ICP iterative registration is performed on the converted coordinates of the test point cloud and model point cloud; point pair pairing distances are calculated through using the kdtree, and distance exceeding points are screened out; the density of a distance exceeding point set is calculated; and whether a foreign object exists is judged. The laser data-based substation foreign object identification method of the invention is used for substation foreign object identification.