Gangliocytic paraganglioma (GP) is a rare neuroendocrine tumor primarily found in the duodenum, most commonly in the second and third sections of the duodenum. Diagnosis of GP is based on its distinctive histopathological characteristics, which include three types of tumor cells in varying proportions: i) Epithelioid, ii) spindle-like and iii) ganglion-shaped cells. The distribution of the three tumor cell components varies from case to case and a patient may be easily misdiagnosed if one of the components is predominant. Endoscopic submucosal dissection (ESD) or surgical resection is the ideal treatment for duodenal GP (DGP); however, biotherapy, nuclide therapy, chemotherapy, targeted therapy and immunotherapy can be selected individually for patients with postoperative recurrence, metastasis or not suitable for surgery. In the present study, a male patient with DGP experienced recurrence after ESD surgery, and so received octreotide (Novartis; 30 mg/28 days) for 12 consecutive cycles. The patient had no further symptoms of gastrointestinal bleeding and no new lesions or metastases were observed after 47 months of follow-up.