The invention discloses a processing method of a composite functional fruit juice beverage. Corn and navel oranges are used as raw materials, and white granulated sugar and a composite stabilizer areadded, so that a corn and navel orange composite type functional fruit juice beverage is processed. The compounding ratio of corn juice to navel orange juice is researched, the influence of the addition amount of the white granulated sugar and the addition quantity of the composite stabilizer on the quality of the beverage is researched, single factor experiment is used as base, orthogonal experiment is adopted, the compounding of the stabilizing agent, the compounding ratio of the corn juice to the navel orange juice, the addition amount of the white granulated sugar, and the addition quantity of the composite stabilizer are optimized, the optimal compounding ratio of the raw materials is determined, and the composite type functional fruit juice beverage which is yellowish in color and smooth in mouth feel and has fragrance of the corn and the fragrance of the navel oranges, is obtained.