Gangliocytic paraganglioma (GP) is a rare, benign tumor which is usually found in the duodenum. We here report four recent cases of GP, with successful endoscopic resection in three cases, including a lesion on the ampulla of Vater. In all cases, each lesion had a stalk that facilitated removal using an endoscopic approach. Endoscopic mucosal resection is a feasible and safe treatment if the location, depth, and lymph node status are all favorable and is also helpful for definite diagnosis of unknown duodenal mass. To avoid morbidity resulting from open surgical resection, careful inspection for the peduncle of the GP will help determine the feasibility of endoscopic resection.