The invention discloses an encapsulating material of a new energy automobile battery. The encapsulating material is prepared from the following components in parts by weight: 100 parts of vinyl-terminated silicone oil, 2 to 6 parts of hydrogen-containing silicone oil, 150 to 300 parts of modified aluminum oxide, 0.05 to 0.15 part of a platinum catalyst, 20 to 50 parts of a halogen-free flame retardant, 2 to 5 parts of white carbon black, 0.5 to 1 part of hexamethyl disilazane, 1 to 5 parts of a peroxide vulcanizing agent and 0.5 to 3 parts of a plasticizer, wherein the peroxide vulcanizing agent is prepared from dibenzoyl peroxide and bis(tert-butyl peroxy isopyl)benzene. The encapsulating material prepared through invention formula disclosed by the invention is nontoxic, has no release ofan irritant gas and is environment-friendly and safe, and not only excellent high / low temperature resistance, excellent weather resistance and excellent electric insulation performance are obtained,but also excellent mechanical performance and excellent heat conduction are obtained; during a working process, an effective protection function on a battery is achieved, heat of the battery can be dissipated in time, high-security protection can be provided for the new energy automobile battery, the safety of the battery is increased, the service life of the battery is increased, and occurrence of the accidents of catching a fire and blasting of the new energy automobile battery can be effectively reduced.