The Waldmann's disease or intestinal lymphangiectasia is a rare disease. We observed a case which occurred in a 14 years old boy. The disease was discovered in the screening of an intermittent diarrhea. The diagnosis was suspected on biological signs of protein-losing enteropathy and the presence of lymphangiectasias seen during endoscopy. The lymphography was conclusive showing the abnormal opacification of the mesenteric region. The other examinations were also important to assert the idiopathic origin of the disease.