Gangliocytic paraganglioma is an uncommon tumor, which is usually located in the ampulla of Vater, and may get confused in the differential diagnosis with ampuloma or GIST. Here we present a case of a patient with upper gastrointestinal bleeding as a predominant symptom, objectified by endoscopy an ulcerative polypoid mass at the juxtapilar level, with histological result of gangliocítica paraganglioma after multiple biopsies, and finally surgical resection. The interest of this case is the difficulty for diagnosing, the different treatments and prognosis that this implies, especially for the tumor location, as surgery can lead to great complications.