AbstractCollagen is the most abundant protein found in humans and is fundamental to tissue structure and function. Collagen products used in biomedical research are primarily derived from mammals, and despite being mainly responsible for providing strength to native connective tissue, collagen hydrogels have comparatively low mechanical properties without the use of additional cross‐linking strategies. Alternative sources of collagen, like fish collagen, are emerging as key biomaterials in tissue engineering and regenerative medicine (TERM). By addressing cultural/religious concerns, ease of extraction, absence of mammalian‐derived allergens, and retention of functional motifs, fish collagen has many promising characteristics that make it a suitable alternative to mammalian collagen. Several physical and chemical cross‐linking strategies of fish collagen are explored to create more stable and resilient scaffolds for a variety of TERM applications. This comprehensive review explores how these modifications are optimized in fish collagen hydrogel systems. Herein, the use of fish collagen and their reported sources for TERM research, as well as the types of treatments (including sterilization) used to alter collagen structures and functions, are presented to date.