A method for enhancing sauce flavor including steps of: collection, dilution, denaturation, enzymolysis, enzyme deactivation, centrifugation, secondary enzymolysis, deodorization, Maillard reaction, seasoning, dosing and flexible sterilization of a raw material, salted duck egg white. The by-product, salted duck egg white, not fully used in the food processing industry is recycled as a raw material, which not only saves the cost but also can protect the environment. Hydrolyzed animal protein is obtained through double-enzyme fractional hydrolysis. The degree of hydrolysis is high. The obtained hydrolyzed protein contains no trichloropropanol and is relatively safe, and flavourzyme decomposes bitter peptide, to make the hydrolysate not taste bitter. Some yeast, cooking wine and essence with unique flavor are chosen. Each ingredient is in a reasonable proportion, and the obtained product is delicious and of mellow flavor.