The role of intestinal microbiota in aging and maintaining active longevity is considered. The first part of the article describes the characteristics of a healthy microbiome, its changes during aging, and the composition of the intestinal microbiome of centenarians. The importance of high microbiome biodiversity in maintaining active longevity is emphasized. The role of intestinal permeability and new biomakers that assess its condition (including zonulin) in maintaining health and in the development of intestinal dysbiosis is revealed. Separate groups of microorganisms that are associated with longevity have been identified (such as Verrucomicrobia, which includes Akkermansia), and the important role of the Bacteroidetes – Firmicutes ratio has been noted. The influence of age-associated changes in the microbiome on health, the connection between changes in the microbiome and physical activity, the possibility of using microbiome analysis to predict biological age, and the correlation of microbiome composition with biomarkers of health and disease are discussed.