The invention discloses an arc extinction nozzle for a high-voltage breaker and a preparation method thereof. The arc extinction nozzle comprises the following components in percentage by weight: 5%-10% of aluminum nitride, 1%-15% of boron nitride and the balance of polytetrafluoroethylene resin. According to the arc extinction nozzle disclosed by the invention, inorganic fillers of the aluminum nitride and the boron nitride are compounded and stuffed in composite polytetrafluoroethylene materials, and the stuffing proportion is reasonably allocated, so that the heat conductivity of nozzle materials is obviously improved, the electric arc erosion resistance of the materials is improved, and moreover, the arc extinction nozzle has an excellent mechanical property and a high temperature resistant property. The arc extinction nozzle is used for arc extinguish chambers of an open type breaker, a pot type breaker and a breaker of an all-metal closed type combined electric appliance, and the breaking-closing property of the breaker is improved, so that the operating stability of high-voltage switch equipment is improved.