The authors present a case report of a retired furniture worker who initially presented with a mucin-secreting adenocarinoma of the right ethmoid sinus. He underwent surgical resection, leaving the nasal septum intact, and topical treatment with 5-fluorouracil. He remained disease free. Three years after his initial presentation he was found to have a left nasal polyp on routine examination. This subsequently proved to be a second primary adenocarcinoma. A review of the literature has not shown any other cases of a second primary adenocarcinoma of the ethmoid sinuses.