Since Katerina Tsilingiri proposed the concept of 􀆵postbiotics in 2013 its definition has undergone several changes. Recently the International Scientific Association for Probiotics and Prebiotics ISAPP issued a widely-accepted definition 􀆵Postbiotics is a preparation of inanimate microorganisms and / or their components that confers a health benefit on the host . This paper reviews its preparation techniques biological activities and characteristic advantages. In recent years based on conventional postbiotic preparation techniques new technologies such as technical association pasteurization supercritical carbon dioxide and pulsed electric field have emerged furthemore the postbiotic preparation techniques of symbiotic flora have become mature and the related products exhibited certain efficacy in clinical trial. A lot of literatures confirm that postbiotics enhance health in a multidimensional manner. This review highlights the functional properties of postbiotics such as regulating intestinal flora protecting gastrointestinal mucosa improving immune homeostasis including improving body immunity and preventing allergic diseases inhibiting inflammatory response antioxidant response inhibiting tumor cell proliferation assisting conventional tumor treatment treating neuropsychiatric diseases and regulating metabolism including hypoglycemia hypolipidemia etc. we also tried to elaborate the possible mechanisms on medical application and to share with the readers. Compared with active probiotics postbiotics have more obvious advantages in terms of stability safety colonization free and applicability which make them show more significant potential for development and prospects for application.