Granulocytic sarcoma (GS) is an unusual localized tumor composed of immature granulocytic precursor cells that occurs in extramedullary sites. However, GS involving the oral cavity is rare. We report a case of intraoral GS with an unusual clinical presentation, including a history of chronic myelogenous leukemia in remission, multiple maxillary and mandibular gingival masses mimicking acute inflammation that developed over a short period, complete remission after 1 week of treatment with imatinib mesylate (Gleevec), and no bone marrow or peripheral blood involvement over a 6-month follow-up period. To our knowledge, this is the first report of treatment of intraoral GS with Gleevec resulting in a complete remission.