Many food proteins and peptides were found to possess biological activities beyond basic nutritional values and have great potential as therapeutics. Because of the instability of proteins/peptides to environmental factors, various technologies have been developed for the delivery of therapeutic peptides and proteins. The colonic region of the gastrointestinal tract is an attractive site for protein/peptide delivery and absorption after oral administration. Co-encapsulation of different protein and peptide drugs in a delivery system may provide synergistic effects. We review here medical applications of proteins and peptides derived from food sources by the introduction and discussion of the structure, biological activity, and oral delivery systems.