Mesenteric cystic lymphangiomas are benign tumours arising from the mesentery, and have no known aetiology. Patients might be discovered incidentally to have asymptomatic mesenteric cysts, or they can present with symptoms such as pain, nausea and vomiting. A 27-year-old man presented with vague abdominal pain, loss of appetite, postprandial fullness and significant weight loss. There was no lymphadenopathy, and abdominal examination was unremarkable. CT showed a mesenteric mass and a diagnosis of abdominal lymphoma was suggested. There was no evidence of pulmonary tuberculosis on chest X-ray and the purified protein derivative test was negative. On laparotomy, a 5×9×7 cm sessile cyst containing thick white fluid and arising from the ileal mesentery was found and completely removed. Histopathology proved a diagnosis of mesenteric cystic lymphangioma. The patient made uneventful recovery, and was asymptomatic on clinical follow-up after 6 weeks.