The whitening of the nail cap may be caused by nail trauma, congenital white nail disease, onychomycosis and other diseases. 1. Nail trauma: If the patient’s nails are violently impacted or squeezed, it may cause localized nail plate damage, which will lead to the symptoms of white nail cover. 2. Congenital white nail disease: the cause of the disease is not clear, mostly related to genetic, vitamin deficiency and other factors. The patient’s nails will appear opaque white spots, horizontal white lines and other symptoms. 3. ringworm of the nail: the cause is mainly due to red trichophyton, trichophyton mustache, candida and other skin fungal infections caused by the patient’s nails will appear to change the color of the nails, mostly yellow, white, and stained color and so on. There are many reasons that lead to whitening of the nail cover, and it is recommended that the patient go to the hospital to clarify the cause of the disease.