Duodenal metastases from primary lung carcinoma are uncommon. They usually occur in terminal‐stage disease. Bleeding, as the first presentation of duodenal metastases, is rare. This case reports a rare mechanism of upper gastrointestinal bleeding due to a metastatic involvement of the duodenum and gastroduodenal artery. A 58‐year‐old man with a past medical history of pulmonary carcinoma presented an episode of hematemesis of great abundance with melena. On physical examination, he was afebrile and pale. The biological data found an anaemia with haemoglobin at 6 g/dL. The upper gastrointestinal endoscopy revealed a congestive duodenal lesion with signs of recent bleeding. An angio CT scan localized the bleeding from the gastroduodenal artery. A few hours later, the patient presented a recurrent episode of hematemesis with deglobalization. So we performed a radiologic embolization of the gastroduodenal artery. Haemorrhage as the first presentation of small bowel metastases is rare, especially when these are located in the duodenum, with a poor prognosis. Radiological embolisation could be the best choice for treatment.