Congenital biliary atresia was seen in female siblings, which is the second time in Japan. Jaundice was first seen in both patients at the first week of life. They were born to healthy parents without diseases of the hepatobiliary system. The elder patient died at the age of 10 months without operation. The younger was operated on (hepatic porto-enterostomy roux-Y) at 80 days of age (IIIbn). She was associated with polysplenia and is alive at 7 months after the operation. The Liver biopsy showed slight fibrosis, round cell infiltration and bile stasis. Except that their father was positive for HB antibody, these cases and their parents were within normal limit for our serous virolological studies. The cause of occurense of this disease in siblings was not obtained.
