A 60-year-old lady presented to us with a right upper abdominal mass. With a clinical diagnosis of liver tumor, she was evaluated with abdominal CT, MRI, nuclear scan, tumor markers, USG guided FNAC and other baseline investigations. On evaluation she had a massive right lobe tumor crossing the midline. In view of the ambiguous diagnosis she was subjected to laparotomy where the lesion was judged unresectable and a biopsy was taken. Histopathological examination showed the rare pathology of primary fibrosarcoma of the liver with features of homogeneous, spindle-shaped cells with abundant collagen fibers showing a classic herringbone pattern. Tissue samples were then sent to another referral cancer hospital for immunohistochemistry and immunoreactive vimentin was found in the tumor cells. Electron microscopically, the tumor cells were rich in rough endoplasmic reticulum without a basement membrane, and were surrounded by large amounts of collagen fibers. The fibroblastic character of the tumor cells was suggested by light and electron microscopy.