A 82-year-old man with anemia underwent upper endoscopy, and a hemorrhagic type 1 tumor was detected on the posterior wall of the duodenal bulb. This patient was diagnosed with neuroendocrine carcinoma(NEC)using biopsy. Distant metastasis was not found on imaging. He was referred to our department for the purpose of surgical therapy and underwent pancreaticoduodenectomy. Based on pathological findings, we diagnosed this patient as having NEC. No postoperative adjuvant chemotherapy was administered, but outpatient clinical follow-up was performed. The patient achieved 16 relapse-free months after surgery. Among the cases of NEC with a primary tumor arising from the digestive tract, cases of NEC of the duodenum that are not papillary carcinoma are rare. We report this case in along with a literature review.