Duodenal lipoma, especially when it is located at bulb, is an uncommon tumor of the gastrointestinal tract. It is usually asymptomatic and found incidentally during roentgenologic study. A 40-year-old female presented intermittent dull abdominal pain. Endoscopy showed a pedunculated polyp in the duodenal bulb. It was excised ad proved to be lipoma. The characteristics, diagnostic procedures and managements of this unusual lesion were discussed.