Because collagen is highly conserved in biological evolution, the structure of fish collagen is similar to other collagens, laying a structural foundation for its partial replacement of mammalian-derived collagen for translational medicine. Taking type I fish collagen as an example, its molecule has a typical triple helix, which is [α1][α2] structure, and the molecular weights of α1 and α2 are about 120 kDa and 110 kDa, respectively. However, unlike mammals such as pigs and cattle, fish are ectothermic animals, and their collagen structure is also specific, and the imino acid content (the sum of proline and hydroxyproline content) in its amino acid composition is significantly lower than that of Collagen derived from terrestrial mammals, therefore has a low degree of intermolecular cross-linking and poor thermal stability.