Nasal masses in the pediatric population present with nasal obstruction, epistaxis and chronic rhinorrhea. We report on a 6-year-old boy with long-standing nasal obstruction. A large left nasal mass was evident on physical examination and CT scan. Techniques of functional endoscopic sinus surgery were used to resect the mass, which, on pathologic examination, proved to be a hamartoma. Hamartomas are non-neoplastic malformations, or inborn errors of tissue development. They are characterized by an abnormal mixture of tissues indigenous to that area of the body. Review of the literature revealed 5 previously reported cases of nasal hamartomas, only 2 of these in children. Our case is unique in that the hamartoma arose from the ethmoid and maxillary sinuses; previously reported cases arose from the septum and vestibule. This is the first reported case treated using a functional endoscopic sinus surgery approach.