With people's quality of life improves， so does their concern for disease and health. Instead of focusing on medical devices and pharmaceutical ingredients for the treatment of disease， people are gradually becoming more aware of emerging substances， ingredients or processed products that play a preventive， ameliorative or supportive role in mitigation. The role of these substances in the body is more focused on the maintenance of physiological functions or the promotion of health through regular external intake. The basic requirement for externally ingestible substances is safety of consumption， and the new labels of no side effects， variety， diversity， efficiency and convenience will be of interest to people in the future. Regular intake of probiotic products with safety certification is considered a safer and more common way to improve human health and alleviate diseases， while the low survival rate of probiotics and the high requirements for their functioning make them difficult to prepare on a large scale， to transport and store for long periods of time， and to ensure their action characteristics. Until now， various preparation and storage methods to ensure the high activity of probiotics have been continuously studied. In recent years， along with the in-depth research on probiotics， it has been found that postbiotics obtained from probiotics through different preparation methods can also have a positive effect on the organism， and have the characteristics of stability and convenient storage and transportation that probiotic products do not have， which may become a new direction to improve the organism's condition or enhance the function of the organism in the future. This paper summarized the various functional effects of postbiotics on the body and the applications of their related products in various fields.