The invention discloses a cable section structure measuring and calculating method. The cable section structure measuring and calculating method comprises the steps that an image of the cable sectionis obtained; the image is binarization-processed, and a corresponding grayscale image is obtained; according to pixel points of the grayscale image, a calculation section parameter corresponding to the cable section is determined, and the calculation section parameter comprises the insulation layer thickness, the shielding layer thickness and/or the insulation layer eccentricity degree; and the calculation section parameter is converted to an actual section parameter of the cable section by using image conversion coefficient. According to the cable section structure measuring and calculating method, the actual section parameter of cable section can be obtained directly through image processing, cables do not need to be sliced up, therefore, it is not necessary to consider influence of theslicing technology on the measuring and calculating accuracy, the measuring and calculating speed is much higher than the speed of a laboratory measuring and calculating method, the time required forinspection is greatly shortened, all cables can be inspected, and reliability of the whole batch of the cables is improved. The invention further correspondingly discloses a cable section structure measuring and calculating system and device, and a readable storage medium.