Grounding devices are an important foundation to ensure the safe and stable operation of power equipment and personal safety. Domestic grounding devices are mainly made of corrosive metal materials such as carbon steel. With the increase in operation time, it is difficult to avoid corrosion fracture and other problems, which is easy to trigger overvoltage, tripping, and other accidents caused by grounding device corrosion. Therefore, it is significant to study the corrosion characteristics and diagnosis technology of grounding devices, which can effectively avoid power accidents caused by grounding device corrosion. From the perspective of the corrosion characteristics of grounding devices, this paper introduces the corrosion mechanism of carbon steel grounding materials, the corrosion characteristics of common grounding materials, the corrosion characteristics of soil, and the influence of current on the corrosion of grounding devices. The characteristics of anti-corrosion measures for various grounding devices are analyzed; the advantages and disadvantages of electrochemical corrosion diagnosis method, electrical network diagnosis method, and electromagnetic field analysis diagnosis method are analyzed and compared; ac-cording to the actual corrosion of grounding devices, the challenges faced by the existing studies are summarized. To accurately diagnose the actual corrosion degree of the grounding device and evaluate the transient response characteristics of the actual corroded grounding devices, it is suggested that the next studies focus on solving the corrosion problems between different grounding materials, the quantification and diagnosis of the actual corrosion degree of the grounding device, transient response characteristics of the actual corroded grounding devices, etc.