Abstract: The clinical data of 12 cases with subungual exostosis were retrospectively analyzed.  Of 12 cases, 5 were male and 7 were female, the age ranged from 5 to 69 years old with median age of 28.83. The lesions located on the toes in 9 cases and on fingers in 3 cases. All cases were treated with surgical excision. There was no recurrence after 3 months to 1 year follow-up. Subungual exostosis usually manifested as a hard, subungual nodule that elevated the nail plate, some with pain and deformed or defected nail plates. Radiograph of the digit demonstrated the subungual bony proliferation. Histologically, the cartilaginous cap of exostoses was made of fibrocartilage, composed of 4 layers (from the outer surface to the inner base): fibrous zone representing periosteum, active fibroblast proliferation zone, fibrocartilage zone, trabecular bone formation zone.