Biopolymers are playing a vital role in biomedical applications. Among them, protein-based biopolymers are utilized for the fabrication of tissue-engineering constructs, therapeutic molecule delivery carriers, emulsifiers, and food packaging materials. Wide ranges of proteins are extracted from animal or plant sources and are being utilized for the fabrication of scaffolds for regenerative tissue-engineering application. Here, an overview about the protein structure, extraction procedure, solubility, and various formulation-based proteins found in the literature are discussed. Biopolymers display several advantages such as biocompatibility and degradability by enzymes. Methods to overcome the disadvantages of these proteins such as immunogenicity, antigenicity, and solubility are reported. Various crosslinking reagents specific to protein chemistry are discussed as well.