Gingival hyperplasia is a rare condition but it is important for cosmetic and mechanic reasons and because of its potential as an indicator of systemic disease. Gingival fibromatosis may exist as an isolated abnormality or as part of a syndrome. In this article a case that was diagnosed clinically and histologically as idiopathic gingival fibromatosis is presented. Patient with gingival hyperplasia should be examined to exclude other reasons to determine the idiopathic gingival fibromatosis or not. Treatment is not required in all cases of idiopathic gingival hyperplasia. Surgical excision is indicated if mechanical problems exist. Recurrence has not been reported.