Introduction: Gingival fibromatosis is rare condition. Clinical features is an enlargement of gingiva, pale pink gingiva with firm consistency without bleeding, can occur both in maxilla or mandible. Gingival enlargement caused by many factors, including inflammatory conditions, side effects of systemic drugs, hereditary or idiopathic. Here, we reported a rare case of gingival fibromatosis. Case Report: A 7-year-old girl was referred from department of Pediatric Dentistry to department of Oral Medicine in dental hospital of Universitas Indonesia with chief complaint of gingival enlargement throughout maxillary and mandible. The condition was noted 3 years back when she was 3.5 years old. This condition did not found in any member of family, and there was no history of taking any medication. Patient said she don’t feel comfortable because of the condition. Intra oral examination, it was seen that a complete enlargement of maxillary gingiva and mandible was the same around, bleeding did not exist. Patient we referred to department of Periodontology for preparation of biopsy, histopathology result is consistent with gingival fibromatosis. Conclusion: Gingival enlargement can cause by many factors, in this case report gingival fibromatosis is due to idiopathic con-dition. Dentists must be able to distinguish the causes of gingival enlargement so that they are expected to be able to manage properly and correctly.