Abstract: With the increasing requirements for insulation eccentricity of medium and low voltage cables in the construction of State Grid, cable enterprises sometimes have unqualified cable insulation eccentricity in production process. In order to explore the reasons for unqualified insulation eccentricity of 35 kV and below medium-voltage cables in production process, influencing factors such as conductors, insulation layers and extrusion molds were analyzed, and corresponding solutions were proposed. Through the verification of insulation eccentricity of 35 kV and below medium-voltage cables, results showed that proposed improvement measures could effectively control cable insulation eccentricity, and fully meet the needs of the State Grid construction.