Kokumi taste, a sensory attribute that enhances flavor complexity, continuity, and mouthfulness without being a basic taste, has gained significant scientific attention. This review synthesizes advances in kokumi peptide research, focusing on their flavor-enhancing mechanisms, receptor interactions (notably calcium-sensing receptors), natural sources, and food applications. We critically evaluate global research progress and key debates, such as receptor synergy mechanisms and limitations of current flavoring mechanism. Future directions emphasize establishing a global kokumi peptide database, developing artificial intelligence-driven prediction platforms, improving in vivo validation, and optimizing industrial-scale production. This review aims to provide a theoretical foundation for food flavor science and to facilitate the integration of kokumi peptides into the development of functional foods and flavor enhancers.