Vitamin D, as a steroid hormone, can promote intestinal calcium and phosphorus absorption, help the human body maintain the balance of calcium and phosphorus levels, and also promote bone mineralization, regulate bone homeostasis, and play an important role in the treatment of osteoporosis and other diseases. With the increasing problem of vitamin D deficiency worldwide, the attention of various disciplines to vitamin D has been increasing in recent years, and it has been found that vitamin D has a wide range of effects in the human body and has a good application prospect in a number of fields. This paper summarizes and analyzes the research progress of vitamin D in the fields of osteoporosis, cardiovascular disease, frailty and sarcopenia, diabetes in the elderly common diseases, in order to improve the attention to vitamin D in the clinical treatment of common diseases in the elderly.