Depressed fingernails are medically known as concave nails and are a skin condition. Concave nail is a nail deformity caused by a number of factors in which the surface of the nail is concave in the center and raised around the perimeter. The cause of this disease is not clear, but can be caused by trauma, long-term exposure to irritants, malnutrition, and hyperthyroidism, Raynaud’s disease and other systemic diseases, mainly manifested as nail depression, nail color change, nail surface roughness or thickening. There is no effective treatment for concave nails, but the main cause of the treatment, it is recommended that patients with concave nails timely medical treatment, by the doctor according to the cause of targeted treatment. Patients should pay more attention to a balanced diet, avoid trauma and direct contact with irritating substances, and move their fingers or toes more often to promote blood circulation.