Embryonal sarcomas of the liver, often called undifferentiated sarcomas or malignant mesenchymomas, are extremely rare tumors that occur chiefly in children with poor prognosis and uncertain histogenesis. Histologically, tumor cells are stellate or spindle shaped, loosely arranged in edematous or myxoid pattern alternating with highly cellular zones and do not show evidence of differentiation. Ultrastructural and immunohistochemical studies by previous investigators indicate that the neoplastic cells are mostly primitive mesenchymal cell which occasionally differentiate to fibroblasts, lipoblasts, histiocytes and smooth muscle cells via intermediate cell types. The authors experienced a case of 6-year old boy who presented with an enlarging abdominal mass of the liver which revealed typical histological and ultrastructural features of embryonal sarcoma with focal areas of unusual chondrosarcomatous differentiation.