Giant duodenal ulcer can be defined as a variant of peptic ulceration that exceeds 2 cm at the greatest diameter. The high mortality and morbidity of giant duodenal ulcer are directly related to the resultant perforation, obstruction and massive hemorrhage. The patient usually has a long history of an inadequately treated or neglected peptic ulcer, but this malady is rarely induced by nonsteroidal anti-inflammatory drugs (NSAIDs). A 60-year-old man was referred to us due to epigastric pain. He underwent appendectomy 1 week ago, and he was administered ketorolac (tarasyn(R)) for 5 days to control the postoperative pain. Esophagogastroduodenos copy (EGD) revealed a giant duodenal ulcer encircling the lumen from the pylorus to the postbulbar portion of the duodenum, and he was then treated with proton pump inhibitor. Two weeks later, the follow-up EGD showed complete duodenal obstruction at the bulb. He was treated by laparoscopic gastrojejunostomy. We report here on this case of duodenal obstruction that was induced by the short-term use of NSAIDs.