In this paper, the mechanical properties and dielectric properties of the blend system of polyolefin elastomer (POE) and polypropylene-based insulation (PPB) are studied, and the influence of elastomer content on material properties is discussed. The research results show that: POE and PPB have good compatibility, the introduction of POE reduces the elastic modulus of the blend system, improves the mechanical properties, and has no significant effect on the melt crystallization behavior of the blend system. In addition, the introduction of an appropriate amount of POE also maintains the dielectric properties of PPB to a greater extent. In summary, the PPB/POE blend system has excellent performance and potential engineering application value, which provides a reference for the development and application of environmentally friendly cable insulation materials.