Jejunal diverticulosis is a very uncommon acquired disease. Clinical manifestations include acute life threatening complication such as perforation, obstruction and bleeding. Jejunal diverticulosis is an extremely rare site of origin of gastrointestinal bleeding, with fewer than seventy cases reported in the literature. We report a 77-year -old patient with a recurrent severe gastrointestinal bleeding manifested by melena and hematochaezia. During the hospitalization the tagged red blood cell scanning was positive for bleeding in the jejunum. At laparotomy, several large-mouthed diverticula at the proximal jejunum were identified. Approximately 30 centimeters of the involved segment was resected with primary end-to-end anastomosis. Postoperative 7 month evolution has been favorable, without any evidence of rebleeding. This report reviews the literature concerning this disease, discusses some diagnostic methods of studying small bowel bleeding and highlights the need to consider this diagnosis in old patients with a gastrointestinal hemorrhage of unknown origin (Rev Méd Chile 2000; 128: 1133-38).