The cause of uneven nails in patients may be caused by iron deficiency anemia, onychomycosis, psoriasis, malnutrition and other diseases. 1. Iron deficiency anemia: It is a common type of ischemia and is related to insufficient iron intake, excessive demand and loss. Patients will have nail abnormalities, thinning, pale nails, or even spatulate nails, thus manifesting as uneven nails in patients. 2. Onychomycosis: manifested by symptoms such as turbid nail plate, separation, uneven surface, hook nail, etc. It is a kind of nail lesion usually caused by dermatophytes invading the nail plate and under the nail, and the patient will have uneven nails. 3. Psoriasis: it is a chronic scaly skin disease caused by genetic factors and environmental factors, inflammation and keratinization abnormality involving the nails is thimble-like or point-like depression, nail separation and other manifestations, patients thus have symptoms of uneven nails. 4. Malnutrition: its etiology is related to insufficient intake of nutrients, consumption dysfunction, physical weakness and other factors. Patients can appear nail growth is slow, easy to fold, thus manifested as uneven nails. There are many reasons for patients to have uneven nails, it is recommended to go to the hospital in time to clarify the cause.