The invention provides an iron tower bolt defect display method and system based on a three-dimensional live-action model. The method comprises: achieving automatic flight of an unmanned aerial vehicle through air route planning, collecting iron tower bolt installation image information, shooting position coordinates (planes and elevations) and shooting angle information, and carrying out POS calculation, aerial triangulation encryption, three-dimensional modeling and the like to construct a live-action three-dimensional model of an iron tower; placing the three-dimensional model of the iron tower on a three-dimensional earth, and analyzing and recognizing the image by using a deep learning intelligent image recognition algorithm; locating the location of a defect, and marking a red colorblock in the three-dimensional scene; and according to the marked defect position on the three-dimensional model, calculating the position coordinates of the bolt defect by using the principle of forward intersection in combination with the position and attitude information of all photos, and carrying out manual checking. According to the invention, with the method and the system, detection of thebolt integrity rate of the power transmission line iron tower is guaranteed, on-site construction acceptance is assisted, the construction quality of the power transmission line is improved, and safety risks caused by human factors are reduced.