Slowly empty nails may be caused by perinail warts, onychomycosis, psoriasis and other diseases. 1. Periungual warts: this disease is caused by human papillomavirus infection and is related to the presence of local skin trauma or impregnation. The main symptom is that the nails appear to be hyperkeratotic, deformed, missing, etc., so some patients will have nails that are slowly empty. 2. Onychomycosis: this disease is caused by dermatophyte infections, such as Trichophyton rubrum, Trichophyton mustelii, etc. It can also be caused by direct infection of tinea pedis, which can be induced by factors such as nail trauma, wearing impermeable shoes, and impaired immune status, etc. Then the patients will have unevenness of the nails, detachment, thickening, and peeling off, etc., and it may be manifested as nails slowly becoming empty. 3. Psoriasis: the cause of this disease is still unclear, may be related to genetics, autoimmune disorders, environmental factors. Common symptoms include nail pitting or thimble-like depression, nail separation and hyperkeratosis under the nail, therefore, patients may have the manifestation of slowly empty nails. It is recommended that patients with slowly empty nails go to the hospital for a complete examination to determine the specific cause of the disease.