Enhancing　the　electrical　performance　of　silicone　rubber　(SiR)　for　cable　accessories　is　noteworthy　as　they　are　almost　the　weakest　parts　of　the　cable　system.　Two　types　of　voltage　stabilizers　were　grafted　onto　the　surface　of　nano-zirconia　(ZrO2)　particles,　and　the　grafted　nanoparticles　were　added　to　the　SiR.　Measurements　such　as　breakdown　strength,　and　conductivity　were　carried　out　to　evaluate　the　electrical　performance　of　SiR　nanocomposites.　The　electrical　performance　measurement　results　indicated　that　the　breakdown　strength　of　the　nanocomposite　SiR　improved　while　the　conductance　current　was　reduced.　The　trap　distribution　showed　that　the　improvement　of　the　electrical　performance　of　the　nanocomposite　SiR　is　mainly　due　to　the　decrease　of　the　shallow　trap　density　or　the　increase　of　the　deep　trap　density.　©　2023　IEEE.