A female infant with hypoproteinemia and coagulopathy associated with hypertyrosinemia was successfully treated with living-related liver transplantation (LRLT). On the 12th day of life plasma amino acid analysis revealed a marked elevation of tyrosine, so the patient was fed on a low-tyrosine and low-phenylalanine diet. However, hepatosplenomegaly, hypotonia, alopecia, eczema and psychomotor delay did not improve and recurrent episodes of disseminated intravascular coagulation (DIC) caused her condition to deteriorate. Liver biopsy on the 230th day revealed marked fatty change accompanied by mild to moderate cholestasis. Therefore, LRLT from her father was performed on the 286th day resulting in improvement of all the aforementioned signs and symptoms. Despite a thorough examination, no diagnosis of a known disorder could be established. However, her elder brother had also been born with severe hypoproteinemia and coagulopathy, and died of DIC on the second day of life. Thus, the disorder is designated as a new entity, namely 'congenital hypoproteinemia and coagulopathy associated with hypertyrosinemia'.