XLPE cable has been widely applied in the grid because of its good electrical properties. Its insulation state directly relates to the safe and reliable operation of power system, how to effectively monitor the insulation state of XLPE cables is very important for power system. In order to meet the needs of power system, XLPE cables metal sheath circulation current on-line monitoring system is designed based on LabVIEW and described the hardware and software designed methods in this paper.