We report on two siblings with early onset lysosomal acid lipase deficiency or Wolman disease. Their parents had a consanguineous marriage. The children showed evidence of abdominal distension and failed to thrive, despite having regular nutrition. At 3-4 months of age, their abdominal distension and jaundice progressed rapidly and they died of liver failure. Sebelipase alfa, a recombinant form of human lysosomal acid lipase has recently been used as an enzyme replacement therapy in patients with later-onset cholesteryl ester storage disease. Therefore, we investigated cases of lysosomal acid lipase deficiency in Japan and found that the number of cases was extremely low. Only 14 cases of Wolman disease and seven cases of cholesteryl ester storage disease were reported. As it is now possible to treat lysosomal acid lipase deficiency, it is important to increase awareness of this disease among pediatricians and doctors working in internal medicine.