Abstract: Buffer layers of high voltage cables have experienced ablation failures which cause significant safety hazards to the power system.In order to solve this problem, ablation status of high voltage cables was analyzed and developed semiconductor repair solution was verified.A solution of ablation failure for buffer layers of high voltage cables was proposed finally, which was to inject semiconductor repair solution into the gap between metal sheath and insulation screen by filling equipment.Ablation development of high voltage cables was suppressed by rebuilding axial electrical connection channel.Besides, failure rate caused by cable erosion was reduced and cable life was extended.This solution was verified in the normal operation of 110 kV cable lines.Through infrared thermal imaging scanning, it was found that all the original erosion hotspots of the cable had disappeared, and the cables had been running well for more than 5 040 h, which achieved a certain repair effect and provided a certain reference value.