The human microbiota is the ecological community of commensal, the aggregate of symbiotic and pathogenic microorganisms that resides on or within any of several human tissues and biofluids. Human microbiota can be considered as a new ‘organ’ due to its important role in maintaining good health. The interaction mechanisms between microbe and host are comprehensive and complex. The dysbiosis of human microbiota is closely related to the process from diseases occurrence to development. Here we outlined the importance of microbiota study and reviewed the current researches worldwide on the links among disease, health and human microbiota.