As one of the six major nutrients in the human body， protein is widely present in various foods， while polyphenols are abundant in plants as secondary metabolites. Proteins and polyphenols produce 'protein-polyphenol complexes' through covalent and non-covalent interactions， which mostly occur spontaneously in food and significantly affect the functional properties and quality of food. In this paper， the formation mechanism of protein-polyphenol complexes and the modern analysis and detection techniques and methods to characterize the interaction of the complexes were reviewed. Effects of protein-polyphenol complexes on their biological activities and their potential applications in emulsions， films， and delivery systems. The purpose was to provide a theoretical basis for the in-depth study of protein-polyphenol complexes， and to provide new ideas for the high-quality utilization and product development of proteins and polyphenols.