This technology focuses on the upcycling of seafood processing by-products into high-value pet food ingredients. Through raw material safety assessment, nutritional profiling, enzymatic hydrolysis, and product formulation design, underutilized materials such as fish skin, bones, connective tissues, and trimming residues are converted into functional pet food applications. The developed products may include pâté-type complete meals, liquid palatability enhancers, collagen-rich fish skin chips, and freeze-dried fish treats. These products feature high protein content, collagen, Omega-3 fatty acids, good palatability, and sustainable resource utilization. By integrating seafood circular economy concepts with functional pet food development, this technology provides a practical pathway for reducing processing waste while creating market-oriented, value-added pet nutrition products.