Duodenal gangliocytic paraganglioma derived from neural crest is a peculiar neuroendocrine tumor. It is incidentally found during radiographic studies or due to gastrointestinal hemorrhage caused by frequent ulceration of the overlying mucosa. Most lesions are pedunculated and submucosal with distinctive histology consisting of endocrine cells, ganglion cells and spindle-shaped Schwann cells. We experienced a duodenal gangliocytic paraganglioma in a 40-year-old woman presenting with episodes of melena. Esophagogastroduodenoscopy revealed a submucosal ulcerated tumor in the second portion of duodenum and a biopsy confirmed gangliocytic paraganglioma. The tumor was enucleated through a duodenotomy. It's size was 5.5 X 3 X 1.5 cm sized and revealed positive cellular reaction for chromogranin, synaptophysin, neuron-specific enolase, and neurofilament by immunohistochemistry. The majority of the reported duodenal gangliocytic paraganglioma were of benign nature. Therefore, radical surgery or a lymph node dissection could be avoided if that disease was confirmed. However, thorough investigation for lymph node metastasis and postoperative follow-up are needed. We report the first case of a duodenal gangliocytic paraganglioma in Korea with a review of literature.