The invention provides an iron tower deformation measuring device and a method thereof. The device comprises a first camera device, a second camera device, an image collecting device and a processor. The first camera device and the second camera device are installed at the different positions, and used for shooting the images before and after the deformation of an iron tower. The image collecting device is connected with the first camera device and the second camera device, and used for collecting the images before and after the deformation of the iron tower which are shot by the first camera device and the second camera device. The processor is connected with the image collecting device, and used for using the images before and after the deformation of the iron tower, and calculating to obtain the displacement of the monitoring point on the iron tower before and after the deformation of the iron tower according to the binocular vision measurement principle. The device is capable of losslessly, accurately, conveniently and rapidly measuring the deformation situation of the iron tower.