SummaryA preterm (gestational age 34 weeks), small for gestational age infant (birth weight <P2,3) is described. Because of unexplained slightly disturbed liver function tests at age 2 months, extensive metabolic examinations were performed. Elevated blood levels of very long‐chain fatty acids, pipecolic acid and abnormal levels of bile acid intermediates were detected, suggesting a peroxisomal disorder. The plasmalogen content of erythrocytes was decreased. Morphologically distinct peroxisomes were absent in the liver. In fibroblasts an accumulation of very long‐chain fatty acids, decreased activity of acyl‐CoA: dihydroxyacetone phosphate acyltransferase and impairedde novo biosynthesis of plasmalogens was found.In summary, a mild variant of the classical cerebro‐hepato‐renal syndrome of Zellweger was found without the characteristic clinical facial signs.