Mussel adhesive proteins have received increased attention as potential biomedical and environmentally friendly underwater adhesives thanks to their fascinating properties, including strong and flexible adhesion, adhesion to various material substrates, water displacement, that they are harmless to human body, and controlled biodegradability. Several mussel adhesive proteins have been identified and characterized from mussels, and profound biochemical knowledge for mussel adhesions has been accumulated. In addition, a lot of effort has been put into realizing the promise of these bioadhesive materials from marine mussels. Here, progress in the diverse developmental approaches, with particular emphasis on functional production of mussel adhesive proteins, are reviewed.