A patient with a history of a laparoscopic gastric bypass presented with a perforated duodenal ulcer. The ulcer was laparoscopically oversewn, and an omentoplasty was performed. Postoperatively, a broad spectrum antibiotic and a proton pump inhibitor were administrated. Several questions arise regarding the diagnosis and treatment of duodenal ulcers after gastric bypass. What are the diagnostic tools to detect a duodenal ulcer, and how should Helicobacter pylori be diagnosed after gastric bypass? The key question is whether the bypassed stomach should be resected as a definitive treatment for complicated duodenal ulcers.