Abstract: Insulation sheath of high voltage power cables is a crucial component of cable system, and its quality directly impacts the stability of the power supply and lifespan of cable. This paper aims to analyze the causes of ablation of the insulating sheath of high voltage power cables and proposes solutions. Through theoretical analysis and simulation calculations, the study explores the impact of factors such as grounding circulation, ground potential, and grounding resistance on sheath ablation. The results show that excessive metal sheath circulation, floating voltage, and increased grounding resistance are the main reasons for ablation. Simulations have verified the changes in sheath voltage under different grounding conditions. Solutions include reducing metal sheath circulation, minimizing floating voltage, enhancing online monitoring, and improving operational management. Ultimately, this paper provides scientific guidance for the design, installation, and maintenance of cable lines, ensuring the safe and stable operation of high voltage cables.