Abstract: Ground corrosion is closely related to the shape of conductor section. By conducting non-uniform corrosion analysis on the cross-section of grounding conductors,the impact of different forms of local corrosion on the grounding conductivity of steel grounding bodies is quantitatively analyzed. Firstly,the complexity of pitting corrosion morphology is taken as the quantitative basis for local corrosion analysis,and the finite element modeling and calculation method of grounding current under the condition of non-uniform corrosion of conductor cross section is proposed in combination with different local corrosion morphology. Secondly,the cross-sectional current density,electric and magnetic field distribution patterns under different corrosion forms are analyzed,as well as the electromagnetic field distribution characteristics of grounding conductor cross-section under non-uniform corrosion conditions. Finally,quantitative analysis is conducted to the influence of different pore corrosion morphology on the conduction impedance per unit length,providing basic model parameters for corrosion diagnosis and grounding analysis. The proposed corrosion detection scheme can distinguish certain local corrosion forms through the power frequency DC ratio,provide a new approach for the diagnosis of steel grounding corrosion.