A gastro-duodenal fourth segment fistula following a penetrating benign gastric ulcer is extremely rare to be found. To the best of our knowledge, our case is the eighth case to describe the gastro-duodenal third and fourth segment fistula, and it is the third to be diagnosed in living patients as all the other cases were diagnosed in autopsies. The case, we are presenting, is of an elderly patient with severe peptic symptoms and a primary diagnosis of gastric outlet obstruction. During our indicated surgery, we accidently diagnosed this rare type of fistula. In the following article, we will describe the clinical features of this fistula, discuss the steps of our unique surgical management, and summarize our follow-up for the patient.