The　electrical　property　parameters　are　crucial　elements　in　the　design　of　cable　accessories,　emphasizing　the　significance　of　precisely　understanding　their　operational　characteristics.　This　study　investigates　the　variations　in　the　electrical　properties　of　silicone　rubber　(SR)　insulation　under　mechanical　stretching.　The　distribution　characteristics　of　relative　permittivity　and　ac　breakdown　strength　are　determined　based　on　the　mechanical　stretching　state.　Furthermore,　the　electric　field　strength　and　safety　margin　are　calculated　to　assess　the　operational　capability　of　cable　accessories.　Comparatively,　the　mechanical　stretching　effects　lead　to　increased　electric　field　strength　and　breakdown　strength,　ultimately　enhancing　the　safety　margins　of　cable　accessories,　with　a　noticeable　impact　as　the　stretching　degree　increases.　These　findings　suggest　that　the　cable　accessories　exhibit　a　higher　safety　level　than　initially　anticipated　and　that　mechanical　stretching　should　be　thoroughly　considered　in　their　design.　©　1994-2012　IEEE.