We describe a case of duodenal, third portion, segmental resection for gastrointestinal stromal tumor. A 76-year-old man was referred for gastrointestinal bleeding, dyspnea and asthenia. Esophagogastroduodenoscopy showed a duodenal bleeding fistula. Computerized tomography demonstrated a retroperitoneal mass that compressed and displaced forward the third duodenal tract. Segmental resection of the third portion of the duodenum with a subtotal gastrectomy was performed. The patient was reconstructed with a termino-terminal duodenal anastomosis of the second and the fourth tract and with a Roux-en-Y gastrojejunum anastomosis. There were no postoperative complications. This duodenectomy procedure could be useful as a less extensive resection for duodenal gastrointestinal stromal tumor located in the third portion of the duodenum when the tumor is well capsulated, when the surrounding structures are not infiltrated and when there are no vascular difficulties. The technique reduces the morbidity and mortality correlated with duodenocefalopancreasectomy and improves postsurgical quality of life without worsening the risk of recurrence.