The ameloblastoma is a benign odontogenic tumor of epithelial origin. Histopathologically, it occurs in six patterns: plexiform, follicular, acanthomatous, granular cell, basal cell, and desmoplastic type. This report presents a rare case of an ameloblastoma in the maxillary sinus that consists of three types: follicular, plexiform, and acanthomatous. The diagnostic procedure, surgical therapy, and follow-up findings are described and discussed.