Chylous ascites is a rare clinical entity often secondary to a lymphoma. In peritoneal dialysis even mild chylous ascites can cause cloudiness of the peritoneal effluent and thus lead to early diagnosis. Twelve cases of chylous ascites (defined by the presence of chylomicrons) among 230 patients with chronic renal failure treated in two peritoneal dialysis centers (Limoges and Saint-Pierre de la Réunion) are reported. A malignancy was encountered in only two cases (a B-cell lymphoma and an ovarian cancer). In the other cases, a precise diagnosis was difficult to establish and was only presumed. Thus chylous effusion in seven cases seemed secondary to cirrhosis, chronic pancreatitis, systemic amyloïdosis or cardiac failure. In three cases the cause was unknown, although microtrauma due to the Tenckhoff catheter was highly suspected. Chylous ascites lasted more than two years in four cases. The long-term nutritional consequences did not justify a change in the method of dialysis.