Koebner phenomenon is observed in a number of inflammatory skin diseases. Psoriasis is one of the most common skin diseases associated with Koebner phenomenon. Nail psoriasis may be developed independently from inflammatory arthritis and skin psoriasis. This study reports on the reconstruction of third web of a 30-year-old woman, which performed on her right, due to congenital syndactyly. Four months postoperatively, she developed nail dystrophy, onycholysis and onychorrhexis of the middle, ring and little fingernails. The clinical and histopathology findings were compatible with diagnosis of isolated nail psoriasis.