The invention belongs to the technical field of building deformation measurement, and specially relates to a method for detecting the verticality of a high tower based on three-dimensional laser scanning. The method comprises the steps: 1), enabling the horizontal distance between a fixed instrument and a tower not to be less than 3/2 of the height of the tower, and obtaining the body point cloud data of a 1/3 circular segment of the vertical projection of the tower; 2), building a 1/3 circular body TIN model, carrying out the fitting of the upper and lower centers of the circular tower, and extracting the section of the tower; 3), calculating the central coordinates of the section of the circular tower, wherein any three non-collinear points on the section can determine a unique circular plane; 4), calculating the longitudinal and lateral inclined components and slope of the tower through the obtained central coordinates of the bottom and top of the circular tower. The method irons out the defects that a conventional verticality detection method for the high tower is difficult in outdoor operation, is difficult in precision control, consumes a large amount of time and manpower, is poor in target data accuracy and is big in data limitation. The method can achieve the detection of the verticality of the high tower quickly at high precision, and has important significance to the detection and monitoring of the similar projects.