Osteoporosis and vascular calcification are both degenerative diseases associated with aging, and affected by a variety of factors. The occurrence and development of the 2 diseases are closely related to calcium and phosphorus metabolism. Recently, there are many studies concerning their common pathogenesis. One of the hot spots is fibroblast growth factor-23 (FGF23)-Klotho axis. This article mainly elaborated its roles in the comorbidity of osteoporosis and vascular calcification.