Hepatoblastoma is a rare childhood embryonal malignancy. Recent reports suggested a linkage between premature birth and later development of hepatoblastoma. In August 2000, we encountered a 24-month-old boy with extremely low birth weight who developed hepatoblastoma with an unfavorable histology. His birth weight was only 584 g. Radiological evaluation of the liver revealed a hypoattenuated tumor occupying the left lobe. His initial serum alpha-fetoprotein level was 4032 ng/mL. The patient underwent successful left hepatectomy. The histological examination showed that the tumor, weighing 210 g, was a hepatoblastoma of epithelial type in two different patterns. One was composed purely of fetal type of tumor cells, whereas another was made up of embryonal type of cells in a macrotrabecular pattern. Four courses of adjuvant chemotherapy were given after surgery and were well tolerated. The patient remained in clinical remission 18 months after diagnosis.