The utility model relates to the technical field of grounding grid measurement. The device is a grounding grid corrosion measuring device based on a stepping frequency continuous wave ground penetrating radar. The system comprises a stepping frequency continuous wave ground penetrating radar. The stepping frequency continuous wave ground penetrating radar comprises a communication and interface unit, a sampling control unit, a stepping frequency transmitter, a superheterodyne receiver, a transmitting relay, a receiving relay, a ground penetrating radar transmitting antenna and a ground penetrating radar receiving antenna. The sampling control unit is connected with the stepping frequency transmitter, the superheterodyne receiver, the transmitting relay and the receiving relay. According tothe utility model, the stepping frequency continuous wave ground penetrating radar is used for detecting the grounding grid; the frequency of the stepping frequency continuous wave ground penetratingradar is adjustable. The response frequency and the phase factor of grounding grid corrosion can be found, the response frequency and the phase factor serve as abnormal factors to detect the grounding grid and extract the abnormal factors of the grounding grid, the abnormal factors are combined with three-dimensional imaging, the specific condition of grounding grid corrosion is comprehensively judged, and the detection recognition rate of grounding grid corrosion is increased.