Desmoid tumors are rare neoplasms accounting for 0.03% of all neoplasms and have an estimated incidence of 2 to 4 per million per year. World Health Organization currently refers to all of the deep types of fibromatosis as desmoid-type of fibromatoses. The term "desmoid" refers to the hard, tendon-like appearance of the tumor. The etiological factors suggested include genetic, endocrine and physical factors. About fifty percent of desmoid tumors arise in the abdominal region. The extra-abdominal desmoid tumors present a difficult problem in recognition and management especially because of the striking discrepancy between its deceptively harmless microscopic appearance and its potential to attain a large size, to recur, and to infiltrate neighboring tissues in the manner of a fibrosarcoma. Desmoid tumors are very rare in the oral cavity with less than 5% of cases constituting oral soft tissue fibromatosis. A 22-year old mentally retarded female patient with desmoid tumor occurring in the tongue is presented here.