Abstract: Hereditary gingival fibromatosis is slowly progressive enlargement of gingival characterized by a generalized enlargement of the buccal and lingual aspects of the attached and marginal gingiva. A case of 14 years old female is reported who has generalized moderate to severe gingival overgrowth of the maxillary and mandibular arches. The diagnose was based on clinical, radiographic and familial history. The treatment included gingivectomy combined with open flap debridment.