The present invention discloses a preparation method of shellfish high F value oligopeptides. The preparation method comprises the following steps: shellfish meat is washed clean, the washed shellfishmeat is homogenized, then enzymatic hydrolysis is conducted to obtain an upper layer enzymatic hydrolysate, a dendrimer is used to prepare a molecular imprinting material, the molecular imprinting material adsorbs aromatic amino acids in the enzymatic hydrolysate to obtain a high F value oligopeptide solution, and high F value oligopeptide powder is prepared by freeze-drying. The raw materials ofthe product are liable to obtain and cheap, the preparation method is simple and convenient for industrial production, has a product yield of 75% or more, and the product has a F value of 50 or moreand can be used as a dietary source component for patients with liver diseases.