Between 1960 and 1994 cystic fibrosis was found in nine out of 1474 infants investigated for neonatal cholestasis. Four had delay in passing meconium. In all patients cholestatic jaundice was present during the first 48 hours and in three patients cholestasis was complete, mimicking biliary atresia. Serum cholesterol concentrations were normal in all but two children. Sweat chloride was repeatedly above 95 mmol/l in all instances. Three children had another condition enhancing the risk of cholestasis (alpha1-antitrypsin deficiency, hypopituitarism, perinatal asphyxia, and total parenteral nutrition). Liver histology displayed portal fibrosis and inflammation with bile duct proliferation; mucous plugs in bile ducts were observed in only one patient. Only one child died from cirrhosis. These results indicate that cystic fibrosis is not a major cause of neonatal cholestasis. However early signs of intestinal obstruction and low concentrations of serum cholesterol may indicate cystic fibrosis, regardless of liver histology. Neonatal cholestasis has no prognostic value concerning evolution to cirrhosis.