Nail hollow, can be considered with nail fungal disease, lichen planus, or psoriasis and other diseases. 1. Nail fungal disease: mostly caused by direct infection of tinea pedis, the fungus invades the nail plate as well as the subnail tissues leading to nail disease, the invaded nail plate can be cloudy, uneven as well as broken and so on, when the whole nail plate is destroyed, there can be all or part of the shedding, resulting in the nail stripping, making the nails become hollow. 2. Lichen planus: the occurrence and aggravation of this disease is related to immunity, heredity, viral infection and other factors, belongs to idiopathic inflammatory disease, when involving the nails, it can lead to thinning or thickening of the nail plate, and can lead to nail peeling due to atrophy. 3. Psoriasis: its occurrence is related to genetic, environmental and immune factors, belongs to the chronic recurrent inflammatory disease, there can be skin manifestations, such as pimples, scales, etc., when it damages the nails, it can cause the thimble-like depression, which can also lead to nail peeling, keratin as well as dirt at the nail bed, and there is a manifestation of empty nails. There are other causes of empty nails (such as yellow nail syndrome), it is recommended to go to the hospital specialist in time, after clarifying the cause of the disease, follow the doctor’s instructions on the cause of the symptomatic treatment.