Purity and biocompatibility are prerequisites for collagen-based products in medical, pharmaceutical, and cosmetic applications. Investigation of new collagen sources and development of recombinant technologies for high-yield collagen production allow the development of novel biomaterials. Here, we highlight a fascinating natural collagenous material from marine mussels as a potential new source for biomaterial research. Further, we focus on recombinant collagen production and evaluate the feasibility to adapt these technologies for the biotechnological production of mussel byssal collagens.