Cholesteryl ester storage disease is a rare disorder if cholesterol metabolism characterized by excessive hepatic storage of cholesteryl esters. The underlying defect probably is decreased activity of alpha-naphtyl-acetatesterase, a lysosomal acid lipase. The leading symptom in the early stage is a pronounced enlargement of the liver without subjective complaints or other changes in the physical status. Diagnosis can be established by liver biopsy, which will yield characteristic findings, and by exclusion of other storage disease. Histologic examination of the biopsy specimen will show lipid droplets in hepatic parenchymal cells, vacuolated Kupffer cells and focal accumulation of foamy cells. Biochemical analysis of the biopsy specimen will show an increased content of cholesteryl esters. Investigation of media of culture fibroblasts will show decreased activity of lysosomal alpha-naphtyl-acetat-esterase. In addition adrenal calcification has to be ruled out, in order to exclude wolman's disease. The prognosis of the disease will depend upon the degree of liver insufficiency, since lympho-histiocytic infiltration as a secondary phenomenon may lead to septal fibrosis and cirrhosis in children or adolescents in most cases. A case report is given of a 13-year old girl suffering from this disease.