Sardine peptide is a refinement of the protein extracted from a fresh sardine to the peptide with the high purity. In vivo it is easy to absorb because of the natural ingredient of the food origin in a steady oligopeptide about 2-10 amino acid arrays. Sardine peptide is refined and pulverized form of hydrolyzed sardine fillet by commercially available enzymes for food use after inactivating autolytic enzymes in the fillet by heating.