This case has interesting images of huge hydro pneumoperitoneum. It is a rare view in the medical practice and a good point to learn one of the complications of perforated duodenal ulcer and failure of omental patch operation. We reported a case of acute abdominal pain with hydro pneumoperitoneum that appeared as an air fluid line in X-ray. The patient had an omental patch surgery. Two days after the operation he got severe abdominal pain. The X-ray images showed significant huge hydro pneumoperitoneum. He underwent urgent surgical intervention for exploration that detected a large amount of gases, a biliary free fluid and a leak from duodenal ulcer. Omental buttressing was then performed.