The homeostasis of intestinal mucosal barrier function is crucial for maintaining intestinal health. Postbiotics are the processed products of probiotics, mainly including active ingredients such as inactivated bacteria, cell lysates, and metabolites. Sufficient research and experiments have confirmed that postbiotics have similar effects to probiotics in repairing intestinal mucosal damage, enhancing intestinal immunity, and stabilizing the intestinal microenvironment, and are expected to become a new solution for preventing and treating inflammatory bowel disease. This review profoundly expounds on the concept types, functional characteristics, preparation methods, and market prospects of postbiotics. It discusses the current developments in postbiotics in terms of active ingredients, action mechanisms and targets, large-scale industrial production design, and formulation of corresponding product regulations and standards. Challenges and limitations provide an academic reference for the future development and application of postbiotics to prevent and treat diseases related to intestinal dysfunction.