The invention discloses a processing method of a compound vegetable protein beverage, which belongs to the technical field of vegetable protein beverage processing. The processing method comprises: (1), 0.1 to 2.5 parts by weight of almonds, 0.1 to 2.5 parts by weight of walnut kernels, 0.1 to 5 parts by weight of peanut kernels, 0.1 to 12 parts by weight of sweeteners, and 0.1 to 1 parts by weight of composite stabilizers Add it into a preparation container, add water to 100 parts by weight, stir and mix evenly; (2), boil; (3), at 85-95°C, use pressures of 2-10MPa and 15-40MPa to homogenize in sequence; ( 4), filling, sealing, and sterilization; wherein, the composite stabilizer in step (1) includes: 0.1 to 0.45 parts of polyglycerol fatty acid ester; 0.05 to 0.45 parts of sodium bicarbonate or 0.02 to 0.45 parts of sodium tripolyphosphate or Their combination; 0.01-0.1 part of citric acid or 0.02-0.2 part of sucrose fatty acid ester or their combination; in step (1), almonds, walnut kernels and peanut kernels are added to the preparation container in the form of mince or slurry. The compound vegetable protein beverage obtained by the processing method has good stability.