Lymphangioma of the jejunum is a rare disease which may cause massive bleeding. A 29-year-old man was referred to our hospital for evaluation of melena with severe anemia, in whom esophagogastroduodenoscopy and colonoscopy had failed to reveal the origin of the bleeding. Post-contrast CT detected an unenhanced mass in the small bowel. Subsequent double-balloon enteroscopy detected a soft, friable, and flat mass associated with lymphofollicular hyperplasia in the jejunum. Endoscopic tattooing enabled laparoscopic partial resection of the jejunum. Pathologic examination confirmed the diagnosis of cavernous lymphangioma of 45 mm in diameter.