Nail dystrophy is a common dermatological condition: it is a multifactorial nail damage. It often affects all finger and toe nails. The nails become thin, cloudy, deformed and brittle. The nail surface loses its luster and is rough. Longitudinal ridges and nail stripping are often present. Fungal microscopy is negative. The condition gradually resolves with age in some patients. Many skin diseases such as psoriasis, malignant baldness, lichen planus, syphilis, systemic scleroderma, follicular keratosis, palmoplantar keratosis, and progeria can be associated with nail dystrophy. Systemic diseases such as nutritional deficiency, hypothyroidism, and poisoning can also cause it. Other factors such as trauma, frostbite, burns and many local factors can also cause it. Congenital nail dystrophy is a systemic disease caused by congenital ectodermal dysplasia due to autosomal dominant inheritance, or epidermolysis bullosa, or pestle and mortar finger leading to nail formation insufficiency, developmental defects, congenital malformations, or secondary to dominant inheritance. Acquired nail dystrophy causes nail growth deficiency for many reasons, can be directly caused by nutritional deficiency (such as some children nail dystrophy is the result of picky eating), including vitamin deficiency, iron deficiency anemia; can be caused by a variety of acute infectious diseases or other acute diseases caused by the body malnutrition; can also be caused by chronic wasting diseases, especially liver disease, blood circulation disorders, lung dysfunction caused by nail dystrophy; nail dystrophy is also often caused by perinail skin disease and trauma. Direct fungal microscopy and fungal culture are needed to distinguish nail dystrophy from onychomycosis. Nowadays, we often encounter clinical cases in which the nails of adults and some children are thin, cloudy, deformed and fragile. The nail surface loses its luster and is rough. However, the most common cases are longitudinal nail ridges, nail white spots, nail hypertrophy (common causes of psoriasis, eczema, nail fungus), and nail plate pits (i.e., many small holes in the nail plate. (Common causes psoriasis, baldness, eczema).