The invention provides a highly-insulated high-voltage cable terminal. The highly-insulated high-voltage cable terminal comprises a stress cone and an insulating main body; the stress cone is preparedfrom the materials in parts by weight: 70-120 parts of liquid silicone rubber, 30-50 parts of a modifier, 3-6 parts of a maleamic acid and 2-4 parts of a vulcanizer; the insulating main body is prepared from the materials in parts by weight: 30-50 parts of EPDM, 0.8-1.2 parts of maleic anhydride, 15-25 parts of an ethane-butene copolymer, 20-40 parts of chlorinated polyethylene, 8-15 parts of hydrogenated butadiene-acrylonitrile rubber, 10-25 parts of nano SiO2, 2-5 parts of nano carbon black, 0.45-0.75 part of an initiator, 8-15 parts of a plasticizer, 2-4 parts of a silane coupling agent, 100-200 parts of a filler, 4-8 parts of a lubricating assistant, 6-10 parts of an active assistant, 2-3.5 parts of an anti-aging agent and 4-10 parts of a sulfurizing agent; acidified graphite is addedinto the liquid silicone rubber, graphite is pretreated by activation, the specific surface area and the surface hydroxyl number of the graphite are improved, the dispersity of the graphite in the liquid silicone rubber is improved, the generation of space charge is restrained, and the electrical performance of insulation structure is improved.