Background: Irritation fibromas are benign tumors of connective tissue origin that occur in response to chronic irritation or trauma. Case Report: An 84-year-old lady presented with a large exophytic right maxillary gingival lesion with rapid progression over 3-months.  Magnetic resonance imaging demonstrated a large heterogenous lobulated mass of the right maxillary alveolus measuring 4.3×3.9×4.3 cm with extension across the midline but no frank invasion.Histology from excision biopsy confirmed irritation fibroma. Conclusion: While classically benign and indolent, this unusual case illustrates the extraordinary size and aggressive clinical appearance they may demonstrate if left untreated. Awareness of such presentations is important as a differential of a large oral cavity mass.