Abstract: In recent years, metal sheath grounding failure has become one of the primary causes of faults in single-ended grounded high-voltage cables. This study conducts a detailed analysis of the failure mechanism of sheath grounding, establishes an electrical equivalent model for single-ended grounded high-voltage cables, and simulates the electrical characteristics of the metal sheath under two scenarios using PSCAD: increased contact resistance and gap discharge. On the basis, the applicability of ground loop current, infrared thermography, and grounding loop resistance measurement is discussed. Furthermore, the distribution patterns of grounding loop resistance in single-ended grounding systems are investigated based on operational data from the Nantong region. Finally, the study introduces a graded classification standard (mild, moderate, and severe corrosion) and differentiated governance strategies for corrosion at the terminal tail of the cable metal sheath, offering theoretical insights and practical guidelines for operation and inspection management of high-voltage cables.