Bile salt hydrolase (BSH) is an intracellular enzyme which is produced by intestinal flora during the period of growth and reproduction. This enzyme has been suggested to be involved in the host's bile acid balance, lipid metabolism and metabolic responses. Therefore, BSH has always been a research hotspot. Detailed knowledge of BSH structure and substrate preferences is a solid foundation for the development of BSH related products. This review explains the source and distribution of BSH, test method for BSH activity. It also introduces enzymatic properties and genetic organization. Finally, the potential applications of BSH research are briefly discussed. This review would provide theoretical basis for the in-depth research of BSH, developments of related functional foods, and other industry applications.