Abstract: Telomeres are continuously shortened due to incomplete replication of chromosomes, which in turn lead to a variety of diseases. Studies have found that many diseases, including ischemic brain injury, diabetic complications, idiopathic pulmonary fibrosis, and osteoporosis, are associated with telomere dysfunction. Cycloastragenol is the aglycone of astragaloside IV, which has pharmacological effects such as antiaging, anti-apoptosis, anti-fibrosis, immunomodulation, promotion of cell proliferation and wound healing. Cycloastragenol is the only reported telomerase activator in natural products, so it has unique research significance. This review summarizes the research progress in pharmacological effects of cycloastragenol on telomere dysfunction diseases, including aging-related diseases, neurodegenerative diseases, diabetic complications, idiopathic pulmonary fibrosis, etc., as well as the related mechanisms.