Hemangiomas of the gastrointestinal tract and mesentery are uncommon benign vascular lesions. While spontaneous bleeding is the hallmark of the gastrointestinal tumor variant, clinical signs of mesenteric hemangiomas are mostly unspecific. Despite the increasing imaging quality of computerized tomography (CT), in most cases the final diagnosis is established through surgery and histopathologic analysis of a macrobiopsy.We present a case report of a 20-year-old female patient who was admitted with progressive abdominal distension and suffered from persistent abdominal pain for 3 months. A large retroperitoneal tumor mass was detected on the CT scan. Due to radiographic signs of an intraabdominal liposarcoma, an explorative laparotomy was performed revealing a large hemangioma originating from the mesosigmoid.Although rare, gastrointestinal hemangiomas should be kept in mind by oncological visceral surgeons as one differential diagnosis of large intraabdominal tumorous masses, especially in young adults.