The present paper reports on 37 primary tumours of the jejunoileum, of which 19 malignant and 18 benign. The authors emphasize the difficulty of establishing a diagnosis before the onset of one of the dramatic complications in the evolution of tumours of the small intestine. The patients were admitted for the following complications: occlusive syndrome -- 28 cases (72.9%), peritoneal syndrome -- 6 cases (16.2%) and hemorrhagic syndrome -- 3 cases (8.1%). All the patients with a peritoneal and hemorrhagic syndrome had malignant tumours.