A 95-year-old woman who presented with ischemic heart disease was admitted due to a sensation of chest compression. Endoscopy was performed due to anemia which showed an irregular ulcerative lesion in the duodenal bulb which a biopsy revealed to be high-grade neuroendocrine carcinoma. Distant metastasis was found and the patient died from the original disease 3 months after the first medical examination. The result of autopsy was neuroendocrine carcinoma of duodenum and invasion and metastases to multiple organs. We report a case of neuroendocrine carcinoma originating from the duodenum excluding the papilla which is extremely rare in Japan.