The incidence of cystic fibrosis (CF) is very rare in Japanese, while it is frequent in Caucasians. Here we report on three Japanese cases of CF. One of the patients had consanguineous parents. All three patients initially developed meconium ileus, and hepatobiliary and pancreatic changes became more severe as age increased. The DeltaF508 mutation, the most frequent mutation associated with CF in Caucasians, was not found in these patients. To evaluate the relationship between the severity of hepatic lesions and a history of meconium ileus, we examined hepatic lesions in the present three cases, and we reviewed 22 Japanese autopsied cases of CF in the literature. No correlation was found between the incidence of biliary cirrhosis and a history of meconium ileus, because the cases with meconium ileus showed a high mortality during the neonatal period, before biliary cirrhosis developed. The high incidence of meconium ileus in Japanese CF patients may relate to a clinically severe phenotype and reflect a different genetic background between Caucasians and Japanese.