Discussion: Benign liver tumors in children may be divided into two major groups: those of epithelial derivation, including simple cysts, focal nodular hyperplasias and adenomas and those of mesenchymal derivation including hamartomas and hemangiomas. Benign mesenchymal tumors of liver are more common than their epithelial counterparts. The hamartoma is characterized by marked overgrowth of mesenchymal or connective tissue of varying maturity and marked tendency to cyst formation. The mesenchyme may contain minor remnants of liver cells, duct cells and even portal tissue, the most characteristic feature being overgrowth of connective tissue. The lobular architecture is maintained.