Pleomorphic adenoma is the most common benign tumour of the salivary glands, especially the parotid gland. In the present paper we introduce the rare case of a pleomorphic adenoma of the maxillary sinus in a 82-year-old man who was referred to our outpatient clinic with nasal obstruction and occasional events of nose bleeding. Thorough investigation, using endoscopy and computed tomography, revealed a mass extending from the left maxillary sinus to the nasal cavity; the tumour was removed surgically; pathological examination showed a pleomorphic adenoma with no signs of malignancy.