There are many reasons for vertical lines and depressions on finger nails, such as physiological phenomenon, loss of trace elements, onychomycosis, and blood circulation disorders in the extremities. 1. Physiological phenomenon: some people are born with vertical lines and depressions on their fingernails, usually the vertical lines and depressions are not very obvious and do not have any uncomfortable symptoms. 2. Loss of trace elements: the lack of calcium, zinc, iron and other elements in the patient’s body may cause the phenomenon of vertical lines and depressions on the fingernails, mainly due to partiality, picky eating, anorexia and other factors caused by nail malnutrition. In addition, long-term diarrhea can lead to excessive loss of trace elements in the body, thus causing the phenomenon. 3. Ringworm of the nails: ringworm of the nails is caused by fungal infection, which may not only cause vertical lines and depressions on the fingernails, but also cause accumulation of chips under the nails, nail shedding, turbidity and other symptoms. 4. Disorders of blood circulation in the extremities: Raynaud’s disease, scleroderma and many other diseases can affect the blood circulation in the extremities of the human body, thus affecting the nails and causing defects in the nails, such as vertical lines and depressions. There are many reasons for the vertical lines and depressions on the fingernails, if accompanied by uncomfortable symptoms, should be timely medical care, clear diagnosis, do not ignore the symptoms, delay the treatment of the condition.