Duodenal gangliocytic paraganglioma is a rare tumor that characteristically occurs in the second portion of the duodenum and typically presents with gastrointestinal bleeding. Duodenal gangliocytic paraganglioma have a good prognosis after surgical resection but metastatic spread to regional lymph nodes and recurrence may rarely occur. A 41-year-old man underwent pancreaticoduodenectomy for the proposed diagnosis of carcinoma of the ampulla vateri. Macroscopically, the tumor measuring 2,7 cm in its greatest diameter, located in the ampulla without infiltration of the pancreas was detected. Histologically, the tumor composed of epitheloid cells, ganglion cells with abundant cytoplasm and vesicular nuclei, and spindle cells arranged in broad fascicles. Immunohistochemically, tumor cells were strongly positive for S-100 protein, cytokeratin AE1/AE3 cocktail, chromogranin A, and synaptophysin. There was no metastasis in the regional lymph nodes. We present here a rare case of duodenal gangliocytic paraganglioma and review the differential diagnosis of this infrequent tumor.