Introduction Pleomorphic adenoma, also known as mixed tumor, is the most common benign tumor of the major and minor salivary glands. The occurrence of pleomorphic adenoma of the tongue base is very rare, and very few cases have been reported in the literature. Objective The authors present a rare case of pleomorphic adenoma of the tongue base and a review of the literature. Case Report A 55-year-old woman had an extensive cervical mass, with little pain, from the submental level to the level below the hyoid bone. Fiberoptic endoscopic examination showed an extensive mass at the base of the tongue with considerable reduction in the airway. Magnetic resonance image scan revealed a contrast-enhancing mass of heterogeneous density over the base of the tongue of 8 × 8 × 7 cm and a reduction of the hypopharyngeal airway. Biopsy of the lesion was performed along with a tracheostomy due to the bulging tongue base and acute respiratory failure. Histologic examination with an immunohistochemistry study revealed a diagnosis of pleomorphic adenoma. The excision of the tumor was performed by a lateral pharyngotomy approach and the total mass was excised. Conclusion The authors consider the rarity of this case and show that this is the 11th and the largest pleomorphic adenoma reported in the English-language medical literature.