Primary carcinoma of the duodenum is rare, accounting for only 0.35% of all gastrointestinal carcinomas, and carcinoma of the fourth part of the duodenum constitutes approximately 10% of duodenal carcinomas, Since the predominant symptoms of tumors in this part of duodenum are related to upper intestinal obstruction, the diagnosis is usually made late, We report the case of a 66-year-old man who presented with anemia, weight loss, and upper intestinal obstruction, and was found to have advanced primary carcinoma of the fourth part of the duodenum by upper gastrointestinal series and computed tomography (CT). A review of the literature indicates that survival, which is related to nodal status, the grade of the tumor, and surgical results, seems to be longer in patients with carcinoma in this part of the duodenum compared to those with carcinomas in other parts of the duodenum, Moreover, segmentary resection has been reported to achieve a favorable outcome.