The present invention relates to a transformer substation three dimensional modeling method based on laser scanning. The method comprises 1) a transformer substation 3D modeling demand obtaining step of obtaining the transformer substation internal equipment information, the external structure information and the geographic position information of a transformer substation; 2) a data acquisition step of using a three dimensional laser scanner to scan the transformer substation internal equipment and the external structure to obtain the initial point cloud data of the transformer substation internal equipment and the external structure information, and obtaining the geographic position information data of the transformer substation via a GIS; 3) a data processing and storage step of carrying out the de-noising and smoothing processing on the initial point cloud data and the geographic position information data and then storing the data in a server; 4) a step of extracting the processed point cloud data and the geographic position information data from the server separately, and establishing a transformer substation 3D detailed model and a 3D landscape model; 5) a step of fusing the transformer substation 3D detailed model and the 3D landscape model to obtain a transformer substation three dimensional model. Compared with the prior art, the transformer substation three dimensional modeling method based on laser scanning of the present invention has the advantages of being high in acquisition efficiency and data precision, being able to improve the transformer substation modeling precision, etc.