The invention discloses a long-life sealing ring for large-sized hydraulic equipment. The long-life sealing ring is prepared from the following raw materials in parts by weight: 80-120 parts of nitrile rubber, 100-120 parts of high-wear resistance furnace black, 3-5 parts of a multiwalled carbon nanotube, 0.5-1 parts of insoluble sulfur, 1-3 parts of tetrabenzylthiuramdisulfide, 1-3 parts of N-cyclohexane-2-benzothiazolyl sulfonamide, 5-8 parts of indirect process zinc oxide, 1-2 parts of stearic acid 1-2, 1.5-3 parts of 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 1.5-3 parts of a thiourea antiozonant, 5-15 parts of trioctyl trimellitate, 1-2 parts of saturated isoparaffin and 1.5-3 parts of saturated fatty acid ester. The long-life sealing ring has the characteristics of hydraulic oil resistance, high temperature resistance, low temperature resistance, high pressure resistance, wear resistance, ozone resistance and the like; compared with a common sealing ring, the long-life sealingring has the advantages of reliability in the sealing, wide high and low temperature ranges, strong applicability, long life, environmental friendliness and the like.