Background/Aim: Nuclear protein in testis (NUT) carcinoma is extremely rare, occurs in the midline of the body, progresses rapidly and is refractory to treatment; most patients die within a year. Here, we describe a case of maxillary sinus NUT carcinoma presenting with epistaxis and nasal obstruction that was treated as a standard head and neck carcinoma. Case Report: The patient was a 41-year-old male with a left buccal swelling; the diagnosis was made of primary NUT carcinoma of the left maxillary sinus and bone metastasis in the cervical spine. After induction chemotherapy with docetaxel plus cisplatin and 5-fluorouracil, the tumor decreased in size, and the patient was further treated with cisplatin and radiation therapy. One month after that, the tumor remained small, however, lung metastasis was observed. Therefore, nivolumab was administered. Cetuximab and paclitaxel were administered after the lung metastasis worsened, but the patient developed progressive disease and died 11 months after diagnosis. Conclusion: Effective treatments for NUT carcinoma have not yet been established. However, early testing to establish the diagnosis may provide useful insights to guide clinical decisions to improve patient outcomes.