Abstract: The durability and safety of concrete structures have always been a hot topic of research. The degree of corrosion of steel is a key part in evaluating the durability and safety of concrete. Aiming at the problems existing in the steel bar corrosion detection method in actual engineering, this paper uses electrical resistance tomography (ERT) technology to obtain imaging data by using embedded electrodes to inject current to collect voltage based on the 16-electrode ERT system. The image reconstruction was carried out by using the resistance imaging method based on the conjugate gradient method. The experimental design and research on the nondestructive testing of concrete reinforcement corrosion was completed based on the above-mentioned method. The results show that the ERT method can visualize the corrosion condition of concrete reinforcement and can qualitatively analyze the range of steel corrosion area. This study can provide new ideas and references for nondestructive testing of concrete reinforcement corrosion.