Abstract: D-mannose is the C-2 epimer of D-glucose. The production methods of D-mannose include plant extraction, chemical synthesis, and biotransformation. In particular, the biotransformation method has received more and more attention. D-mannose has been found to have a variety of important physiological functions. On the one hand, D-mannose can protect the urinary system by preventing bacteria from adhering to the urothelium. On the other hand, D-mannose can interfere with glucose metabolism, transport and modified anti-cancer drug carriers play an anti-tumor effect. In addition, D-Mannose can regulate the immune system by enhancing the transformation of naive T cells into regulatory T cells (Treg cells). In the future, the physiological functions of D-mannose need to be further confirmed by more research data, in order to provide support for the application of D-mannose in functional foods and biomedicine. This review introduces the recent progress of studies on the production technology, metabolic pathways, physiological functions and application of D-mannose.