Optical fiber composite overhead ground wire ( OPGW) located in heavy icing area of transmission line is likely to suffer fracture accident caused by stress overload when icing in winter． The icing has a strong impact on safe operation of OPGW in heavy icig area． The method of DC de － icing using insulation reconstruction is adopted to eliminate the ice covered on OPGW． Based on the existing research results，taking N56 ～ N80 OPGW，which is in heavy icing area belonging to 110 kV Leiba II line of State Grid Liangshan Power Supply Company，as the research object，the relevant simulation and calculation， including DC de － icing circuit，induced voltage，grounding mode，selection of insulator and insulation reform method for different types of towers，are illustrated． Using the obtained conclusions，the insulation reconstruction project for N56 ～ N80 OPGW of 110 kV Leiba II line has been completed． DC de － icing has been carried out four times from December of 2018 to January of 2019 which has a good de － icing effect，and the line is operating normally． The insulation reconstruction method of OPGW can provide a reference for the subsequent projects．