The invention discloses a method for extracting the bioactive peptide of snails. The method includes the steps of (1) breeding live snails for a week, removing debris, picking out foot flesh to be crushed and stirred to be muddy, grinding by a liquid nitrogen grounding method, and obtaining snail tissue for use; (2) degreasing; (3) conducting digestion; (4) conducting enzymolysis; (5) conducting first dialysis, salting out and purification on enzymolysis products, and then conducting second dialysis and drying to obtain the bioactive peptide. The bioactive peptide of snails can be quickly absorbed by gastrointestinal parietal cells directly, promote the secretion of digestive enzymes, clear low density lipoprotein, reduce erythrocyte viscosity, enhance the elasticity of myocardium and blood vessels, activate lung cells, modify the air-blood barrier, remove the lung toxin, inhibit osteoclast, and regulate osteoporosis, arthritis and the diseases caused by calcium deficiency; in the aspect of an immune system, the bioactive peptide has the functions of stimulating the regeneration of thymus, accelerating the generation of lymph T cells, B cells and NK cells, preventing neoplastic lesions and the like.