Fifteen patients with non-immune fetal or neonatal ascites and absence of generalized edema are described. Nine patients were diagnosed prenatally. Nine patients were preterm. Artificial ventilation was necessary in twelve infants immediately after birth. In five cases, including two cases of transitory ascites, the etiology could not be established. In accordance with previous reports, we found the following underlying disorders in our patients: urinary tract obstruction, polycystic disease of the kidneys, chylous ascites, sepsis, intrahepatic atresia of the biliary ducts, hepatic and renal failure following severe asphyxia. 8 out of 15 patients died. A survey of the literature shows a variety of underlying disorders. Therefore, several diagnostic tests are necessary, in order to identify the etiology. Causative treatment is possible in some cases of urogenital , gastrointestinal, infectious and chylous ascites. Sophisticated perinatal management is essential for the outcome of patients with fetal or neonatal ascites; nevertheless the mortality rate is still about 50%.