Abstract: Selenium-enriched peptides are small-molecule peptides with high selenium content and antioxidant and other bioactivities, in which selenium mainly exists in the form of selenoamino acids. This review summarizes the preparation methods of selenium-enriched peptides, including enzymatic hydrolysis of plant materials, microbial transformation, and chemical synthesis, expounds the structure and physicochemical properties of selenium-enriched peptides, analyzes their roles and mechanisms in antioxidant, antihypertensive, hepatoprotective, immunomodulatory, and antagonistic effects against heavy metals, and explores their stabilization and delivery and their application areas, especially demonstrating their great application potential in the food and pharmaceutical fields compared with selenium-free traditional peptides.