This paper reports the relationship between serum cholesterol level and hepatoblastoma in nine patients. Four of the nine patients had a high (417-544 mg%) serum cholesterol. All of these patients were less than one year of age and had tumors of the epithelial type. Three of the infants died soon after being diagnosed. Three patients had a moderately elevated serum cholesterol (206-249mg%). One underwent primary hepatic resection. Two had nonresectable tumors that became resectable after chemotherapy. One died secondary to pulmonary metastases. The remaining two patients had a normal serum cholesterol level prior to treatment. Both patients had hepatic resection after chemotherapy and had no evidence of increased cholesterol postoperatively and are alive six years after diagnosis. From these data, it is suggested that the pretreatment level of serum cholesterol may be of prognostic significance in infants and children with hepatoblastoma.